Cutis

The Diagnosis: Ecthyma Gangrenosum

Histopathology revealed basophilic bacterial rods around necrotic vessels with thrombosis and edema (Figure). Blood and tissue cultures grew Pseudomonas aeruginosa. Based on the histopathology and clinical presentation, a diagnosis of P aeruginosa–associated ecthyma gangrenosum (EG) was made. The patient’s symptoms resolved with intravenous cefepime, and he later was transitioned to oral levofloxacin for outpatient treatment.

Ecthyma gangrenosum is an uncommon cutaneous manifestation of bacteremia that most commonly occurs secondary to P aeruginosa in immunocompromised patients, particularly patients with severe neutropenia in the setting of recent chemotherapy.^1,2 Ecthyma gangrenosum can occur anywhere on the body, predominantly in moist areas such as the axillae and groin; the arms and legs, such as in our patient, as well as the trunk and face also may be involved.³ Other causes of EG skin lesions include methicillin-resistant Staphylococcus aureus, Citrobacter freundii, Escherichia coli, fungi such as Candida, and viruses such as herpes simplex virus.^2,4-6 Common predisposing conditions associated with EG include neutropenia, leukemia, HIV, diabetes mellitus, extensive burn wounds, and a history of immunosuppressive medications. It also has been known to occur in otherwise healthy, immunocompetent individuals with no difference in clinical manifestation.²

The diagnosis is clinicopathologic, with initial evaluation including blood and wound cultures as well as a complete blood cell count once EG is suspected. An excisional or punch biopsy is performed for confirmation, showing many gram-negative, rod-shaped bacteria in cases of pseudomonal EG.⁷ Histopathology is characterized by bacterial perivascular invasion that then leads to secondary arteriole thrombosis, tissue edema, and separation of the epidermis.^7,8 Resultant ischemic necrosis results in the classic macroscopic appearance of an erythematous macule that rapidly progresses into a central necrotic lesion surrounded by an erythematous or violaceous halo after undergoing a hemorrhagic bullous stage.1,9 A Wood lamp can be used to expedite the diagnosis, as Pseudomonas bacteria excretes a pigment (pyoverdine) that fluoresces yellowish green.¹⁰

Ecthyma gangrenosum can be classified as a primary skin lesion that may or may not be followed by bacteremia or as a lesion secondary to pseudomonal bacteremia.¹¹ Bacteremia has been reported in half of cases, with hematogenous metastasis of the infection, likely in manifestations with multiple bilateral lesions.² Our patient’s presentation of a single lesion revealed a positive blood culture result. Lesions also can develop by direct inoculation of the epidermis causing local destruction of the surrounding tissue. The nonbacteremic form of EG has been associated with a lower mortality rate of around 15% compared to patients with bacteremia ranging from 38% to 96%.¹² The presence of neutropenia is the most important prognostic factor for mortality at the time of diagnosis.¹³

Prompt empiric therapy should be initiated after obtaining wound and blood cultures in those with infection until the causative organism and its susceptibility are identified. Pseudomonal infections account for 4% of all cases of hospital-acquired bacteremia and are the third leading cause of gram-negative bloodstream infection.⁷ Initial broad-spectrum antibiotics include antipseudomonal β-lactams (piperacillin-tazobactam), cephalosporins (cefepime), fluoroquinolones (levofloxacin), and carbapenems (imipenem).^1,7 Medical therapy alone may be sufficient without requiring extensive surgical debridement to remove necrotic tissue in some patients. Surgical debridement usually is warranted for lesions larger than 10 cm in diameter.³ Our patient was treated with intravenous cefepime with resolution and was followed with outpatient oral levofloxacin as appropriate. A high index of suspicion should be maintained for relapsing pseudomonal EG infection among patients with AIDS, as the reported recurrence rate is 57%.¹⁴

Clinically, the differential diagnosis of EG presenting in immunocompromised patients or individuals with underlying malignancy includes pyoderma gangrenosum, papulonecrotic tuberculid, and leukemia cutis. An erythematous rash with central necrosis presenting in a patient with systemic symptoms is pathognomonic for erythema migrans and should be considered as a diagnostic possibility in areas endemic for Lyme disease in the United States, including the northeastern, mid-Atlantic, and north-central regions.¹⁵ A thorough history, physical examination, basic laboratory studies, and histopathology are critical to differentiate between these entities with similar macroscopic features. Pyoderma gangrenosum histologically manifests as a noninfectious, deep, suppurative folliculitis with leukocytoclastic vasculitis in 40% of cases.¹⁶ Although papulonecrotic tuberculid can present with dermal necrosis resulting from a hypersensitivity reaction to antigenic components of mycobacteria, there typically are granulomatous infiltrates present and a lack of observed organisms on histopathology.¹⁷ Although leukemia cutis infrequently occurs in patients diagnosed with leukemia, its salient features on pathology are nodular or diffuse infiltrates of leukemic cells in the dermis and subcutis with a high nuclear-to-cytoplasmic ratio, often with prominent nucleoli.¹⁸ Lyme disease can present in various ways; however, cutaneous involvement in the primary lesion is histologically characterized by a perivascular lymphohistiocytic infiltrate containing plasma cells at the periphery of the expanding annular lesion and eosinophils present at the center.¹⁹

The Diagnosis: Ecthyma Gangrenosum

Histopathology revealed basophilic bacterial rods around necrotic vessels with thrombosis and edema (Figure). Blood and tissue cultures grew Pseudomonas aeruginosa. Based on the histopathology and clinical presentation, a diagnosis of P aeruginosa–associated ecthyma gangrenosum (EG) was made. The patient’s symptoms resolved with intravenous cefepime, and he later was transitioned to oral levofloxacin for outpatient treatment.

Ecthyma gangrenosum is an uncommon cutaneous manifestation of bacteremia that most commonly occurs secondary to P aeruginosa in immunocompromised patients, particularly patients with severe neutropenia in the setting of recent chemotherapy.^1,2 Ecthyma gangrenosum can occur anywhere on the body, predominantly in moist areas such as the axillae and groin; the arms and legs, such as in our patient, as well as the trunk and face also may be involved.³ Other causes of EG skin lesions include methicillin-resistant Staphylococcus aureus, Citrobacter freundii, Escherichia coli, fungi such as Candida, and viruses such as herpes simplex virus.^2,4-6 Common predisposing conditions associated with EG include neutropenia, leukemia, HIV, diabetes mellitus, extensive burn wounds, and a history of immunosuppressive medications. It also has been known to occur in otherwise healthy, immunocompetent individuals with no difference in clinical manifestation.²

The diagnosis is clinicopathologic, with initial evaluation including blood and wound cultures as well as a complete blood cell count once EG is suspected. An excisional or punch biopsy is performed for confirmation, showing many gram-negative, rod-shaped bacteria in cases of pseudomonal EG.⁷ Histopathology is characterized by bacterial perivascular invasion that then leads to secondary arteriole thrombosis, tissue edema, and separation of the epidermis.^7,8 Resultant ischemic necrosis results in the classic macroscopic appearance of an erythematous macule that rapidly progresses into a central necrotic lesion surrounded by an erythematous or violaceous halo after undergoing a hemorrhagic bullous stage.1,9 A Wood lamp can be used to expedite the diagnosis, as Pseudomonas bacteria excretes a pigment (pyoverdine) that fluoresces yellowish green.¹⁰

Ecthyma gangrenosum can be classified as a primary skin lesion that may or may not be followed by bacteremia or as a lesion secondary to pseudomonal bacteremia.¹¹ Bacteremia has been reported in half of cases, with hematogenous metastasis of the infection, likely in manifestations with multiple bilateral lesions.² Our patient’s presentation of a single lesion revealed a positive blood culture result. Lesions also can develop by direct inoculation of the epidermis causing local destruction of the surrounding tissue. The nonbacteremic form of EG has been associated with a lower mortality rate of around 15% compared to patients with bacteremia ranging from 38% to 96%.¹² The presence of neutropenia is the most important prognostic factor for mortality at the time of diagnosis.¹³

Prompt empiric therapy should be initiated after obtaining wound and blood cultures in those with infection until the causative organism and its susceptibility are identified. Pseudomonal infections account for 4% of all cases of hospital-acquired bacteremia and are the third leading cause of gram-negative bloodstream infection.⁷ Initial broad-spectrum antibiotics include antipseudomonal β-lactams (piperacillin-tazobactam), cephalosporins (cefepime), fluoroquinolones (levofloxacin), and carbapenems (imipenem).^1,7 Medical therapy alone may be sufficient without requiring extensive surgical debridement to remove necrotic tissue in some patients. Surgical debridement usually is warranted for lesions larger than 10 cm in diameter.³ Our patient was treated with intravenous cefepime with resolution and was followed with outpatient oral levofloxacin as appropriate. A high index of suspicion should be maintained for relapsing pseudomonal EG infection among patients with AIDS, as the reported recurrence rate is 57%.¹⁴

Clinically, the differential diagnosis of EG presenting in immunocompromised patients or individuals with underlying malignancy includes pyoderma gangrenosum, papulonecrotic tuberculid, and leukemia cutis. An erythematous rash with central necrosis presenting in a patient with systemic symptoms is pathognomonic for erythema migrans and should be considered as a diagnostic possibility in areas endemic for Lyme disease in the United States, including the northeastern, mid-Atlantic, and north-central regions.¹⁵ A thorough history, physical examination, basic laboratory studies, and histopathology are critical to differentiate between these entities with similar macroscopic features. Pyoderma gangrenosum histologically manifests as a noninfectious, deep, suppurative folliculitis with leukocytoclastic vasculitis in 40% of cases.¹⁶ Although papulonecrotic tuberculid can present with dermal necrosis resulting from a hypersensitivity reaction to antigenic components of mycobacteria, there typically are granulomatous infiltrates present and a lack of observed organisms on histopathology.¹⁷ Although leukemia cutis infrequently occurs in patients diagnosed with leukemia, its salient features on pathology are nodular or diffuse infiltrates of leukemic cells in the dermis and subcutis with a high nuclear-to-cytoplasmic ratio, often with prominent nucleoli.¹⁸ Lyme disease can present in various ways; however, cutaneous involvement in the primary lesion is histologically characterized by a perivascular lymphohistiocytic infiltrate containing plasma cells at the periphery of the expanding annular lesion and eosinophils present at the center.¹⁹

The Diagnosis: Ecthyma Gangrenosum

Histopathology revealed basophilic bacterial rods around necrotic vessels with thrombosis and edema (Figure). Blood and tissue cultures grew Pseudomonas aeruginosa. Based on the histopathology and clinical presentation, a diagnosis of P aeruginosa–associated ecthyma gangrenosum (EG) was made. The patient’s symptoms resolved with intravenous cefepime, and he later was transitioned to oral levofloxacin for outpatient treatment.

Ecthyma gangrenosum is an uncommon cutaneous manifestation of bacteremia that most commonly occurs secondary to P aeruginosa in immunocompromised patients, particularly patients with severe neutropenia in the setting of recent chemotherapy.^1,2 Ecthyma gangrenosum can occur anywhere on the body, predominantly in moist areas such as the axillae and groin; the arms and legs, such as in our patient, as well as the trunk and face also may be involved.³ Other causes of EG skin lesions include methicillin-resistant Staphylococcus aureus, Citrobacter freundii, Escherichia coli, fungi such as Candida, and viruses such as herpes simplex virus.^2,4-6 Common predisposing conditions associated with EG include neutropenia, leukemia, HIV, diabetes mellitus, extensive burn wounds, and a history of immunosuppressive medications. It also has been known to occur in otherwise healthy, immunocompetent individuals with no difference in clinical manifestation.²

The diagnosis is clinicopathologic, with initial evaluation including blood and wound cultures as well as a complete blood cell count once EG is suspected. An excisional or punch biopsy is performed for confirmation, showing many gram-negative, rod-shaped bacteria in cases of pseudomonal EG.⁷ Histopathology is characterized by bacterial perivascular invasion that then leads to secondary arteriole thrombosis, tissue edema, and separation of the epidermis.^7,8 Resultant ischemic necrosis results in the classic macroscopic appearance of an erythematous macule that rapidly progresses into a central necrotic lesion surrounded by an erythematous or violaceous halo after undergoing a hemorrhagic bullous stage.1,9 A Wood lamp can be used to expedite the diagnosis, as Pseudomonas bacteria excretes a pigment (pyoverdine) that fluoresces yellowish green.¹⁰

Ecthyma gangrenosum can be classified as a primary skin lesion that may or may not be followed by bacteremia or as a lesion secondary to pseudomonal bacteremia.¹¹ Bacteremia has been reported in half of cases, with hematogenous metastasis of the infection, likely in manifestations with multiple bilateral lesions.² Our patient’s presentation of a single lesion revealed a positive blood culture result. Lesions also can develop by direct inoculation of the epidermis causing local destruction of the surrounding tissue. The nonbacteremic form of EG has been associated with a lower mortality rate of around 15% compared to patients with bacteremia ranging from 38% to 96%.¹² The presence of neutropenia is the most important prognostic factor for mortality at the time of diagnosis.¹³

Prompt empiric therapy should be initiated after obtaining wound and blood cultures in those with infection until the causative organism and its susceptibility are identified. Pseudomonal infections account for 4% of all cases of hospital-acquired bacteremia and are the third leading cause of gram-negative bloodstream infection.⁷ Initial broad-spectrum antibiotics include antipseudomonal β-lactams (piperacillin-tazobactam), cephalosporins (cefepime), fluoroquinolones (levofloxacin), and carbapenems (imipenem).^1,7 Medical therapy alone may be sufficient without requiring extensive surgical debridement to remove necrotic tissue in some patients. Surgical debridement usually is warranted for lesions larger than 10 cm in diameter.³ Our patient was treated with intravenous cefepime with resolution and was followed with outpatient oral levofloxacin as appropriate. A high index of suspicion should be maintained for relapsing pseudomonal EG infection among patients with AIDS, as the reported recurrence rate is 57%.¹⁴

Clinically, the differential diagnosis of EG presenting in immunocompromised patients or individuals with underlying malignancy includes pyoderma gangrenosum, papulonecrotic tuberculid, and leukemia cutis. An erythematous rash with central necrosis presenting in a patient with systemic symptoms is pathognomonic for erythema migrans and should be considered as a diagnostic possibility in areas endemic for Lyme disease in the United States, including the northeastern, mid-Atlantic, and north-central regions.¹⁵ A thorough history, physical examination, basic laboratory studies, and histopathology are critical to differentiate between these entities with similar macroscopic features. Pyoderma gangrenosum histologically manifests as a noninfectious, deep, suppurative folliculitis with leukocytoclastic vasculitis in 40% of cases.¹⁶ Although papulonecrotic tuberculid can present with dermal necrosis resulting from a hypersensitivity reaction to antigenic components of mycobacteria, there typically are granulomatous infiltrates present and a lack of observed organisms on histopathology.¹⁷ Although leukemia cutis infrequently occurs in patients diagnosed with leukemia, its salient features on pathology are nodular or diffuse infiltrates of leukemic cells in the dermis and subcutis with a high nuclear-to-cytoplasmic ratio, often with prominent nucleoli.¹⁸ Lyme disease can present in various ways; however, cutaneous involvement in the primary lesion is histologically characterized by a perivascular lymphohistiocytic infiltrate containing plasma cells at the periphery of the expanding annular lesion and eosinophils present at the center.¹⁹

The Diagnosis: Schwannoma

Schwannoma, also known as neurilemmoma, is a benign encapsulated neoplasm of the peripheral nerve sheath that presents as a subcutaneous nodule.¹ It also may present in the retroperitoneum, mediastinum, and viscera (eg, gastrointestinal tract, bone, upper respiratory tract, lymph nodes). It may occur as multiple lesions when associated with certain syndromes. It usually is an asymptomatic indolent tumor with neurologic symptoms, such as pain and tenderness, in the lesions that are deeper, larger, or closer in proximity to nearby structures.^2,3

Histologically, a schwannoma is encapsulated by the perineurium of the nerve bundle from which it originates (quiz image [top]). The tumor consists of hypercellular (Antoni type A) and hypocellular (Antoni type B) areas. Antoni type A areas consist of tightly packed, spindleshaped cells with elongated wavy nuclei and indistinct cytoplasmic borders. These nuclei tend to align into parallel rows with intervening anuclear zones forming Verocay bodies (quiz image [bottom]).⁴ Verocay bodies are not seen in all schwannomas, and similar formations may be seen in other tumors as well. Solitary circumscribed neuromas also have Verocay bodies, whereas dermatofibromas and leiomyomas have Verocay-like bodies. Antoni type B areas have scattered spindled or ovoid cells in an edematous or myxoid matrix interspersed with inflammatory cells such as lymphocytes and histiocytes. Vessels with thick hyalinized walls are a helpful feature in diagnosis.² Schwann cells of a schwannoma stain diffusely positive with S-100 protein. The capsule stains positively with epithelial membrane antigen due to the presence of perineurial cells.²

The morphologic variants of this entity include conventional (common, solitary), cellular, plexiform, ancient, melanotic, epithelioid, pseudoglandular, neuroblastomalike, and microcystic/reticular schwannomas. There are additional variants that are associated with genetic syndromes, such as multiple cutaneous plexiform schwannomas linked with neurofibromatosis type 2, psammomatous melanotic schwannoma presenting in Carney complex, schwannomatosis, and segmental schwannomatosis (a distinct form of neurofibromatosis characterized by multiple schwannomas localized to one limb). Either presentation may have alteration or deletion of the neurofibromatosis type 2 gene, NF2, on chromosome 22.^2,5

Nodular fasciitis is a benign tumor of fibroblasts and myofibroblasts that usually arises in the subcutaneous tissues. It most commonly occurs in the upper extremities, trunk, head, and neck. It presents as a single, often painful, rapidly growing, subcutaneous nodule. Histologically, lesions mostly are well circumscribed yet unencapsulated, in contrast to schwannomas. They may be hypocellular or hypercellular and are composed of uniform spindle cells with a feathery or fascicular (tissue culture–like) appearance in a loose, myxoid to collagenous stroma. There may be foci of hemorrhage and conspicuous mitoses but not atypical figures (Figure 1). Immunohistochemically, the cells stain positively for smooth muscle actin and negatively for S-100 protein, which sets it apart from a schwannoma. Most cases contain fusion genes, with myosin heavy chain 9 ubiquitin-specific peptidase 6, MYH9-USP6, being the most common fusion product.⁶

Solitary circumscribed neuroma (palisaded encapsulated neuroma) is a benign, usually solitary dermal lesion. It most commonly occurs in middle-aged to elderly adults as a small (<1 cm), firm, flesh-colored to pink papule on the face (ie, cheeks, nose, nasolabial folds) and less commonly in the oral and acral regions and on the eyelids and penis. The lesion usually is unilobular; however, other growth patterns such as plexiform, multilobular, and fungating variants have been identified. Histologically, it is a well-circumscribed nodule with a thin capsule of perineurium that is composed of interlacing bundles of Schwann cells with a characteristic clefting artifact (Figure 2). Cells have wavy dark nuclei with scant cytoplasm that occasionally form palisades or Verocay bodies causing these lesions to be confused with schwannomas. Immunohistochemically, the Schwann cells stain positively with S-100 protein, and the perineurium stains positively with epithelial membrane antigen, Claudin-1, and Glut-1. Neurofilament protein stains axons throughout neuromas, whereas in schwannoma, the expression often is limited to entrapped axons at the periphery of the tumor.⁷

Angioleiomyoma is an uncommon, benign, smooth muscle neoplasm of the skin and subcutaneous tissue that originates from vascular smooth muscle. It most commonly presents in adult females aged 30 to 60 years, with a predilection for the lower limbs. These tumors typically are solitary, slow growing, and less than 2 cm in diameter and may be painful upon compression. Similar to schwannoma, angioleiomyoma is an encapsulated lesion composed of interlacing, uniform, smooth muscle bundles distributed around vessels (Figure 3). Smooth muscle cells have oval- or cigar-shaped nuclei with a small perinuclear vacuole of glycogen. Immunohistochemically, there is strong diffuse staining for smooth muscle actin and h-caldesmon. Recurrence after excision is rare.^2,8

Neurofibroma is a common, mostly sporadic, benign tumor of nerve sheath origin. The solitary type may be localized (well circumscribed, unencapsulated) or diffuse. The presence of multiple, deep, and plexiform lesions is associated with neurofibromatosis type 1 (von Recklinghausen disease) that is caused by germline mutations in the NF1 gene. Histologically, the tumor is composed of Schwann cells, fibroblasts, perineurial cells, and nerve axons within an extracellular myxoid to collagenous matrix (Figure 4). The diffuse type is an ill-defined proliferation that entraps adnexal structures. The plexiform type is defined by multinodular serpentine fascicles. Immunohistochemically, the Schwann cells stain positive for S-100 protein and SOX10 (SRY-Box Transcription Factor 10). Epithelial membrane antigen stains admixed perineurial cells. Neurofilament protein highlights intratumoral axons, which generally are not found throughout schwannomas. Transformation to a malignant peripheral nerve sheath tumor occurs in up to 10% of patients with neurofibromatosis type 1, usually in plexiform neurofibromas, and is characterized by increased cellularity, atypia, mitotic activity, and necrosis.⁹

The Diagnosis: Schwannoma

Schwannoma, also known as neurilemmoma, is a benign encapsulated neoplasm of the peripheral nerve sheath that presents as a subcutaneous nodule.¹ It also may present in the retroperitoneum, mediastinum, and viscera (eg, gastrointestinal tract, bone, upper respiratory tract, lymph nodes). It may occur as multiple lesions when associated with certain syndromes. It usually is an asymptomatic indolent tumor with neurologic symptoms, such as pain and tenderness, in the lesions that are deeper, larger, or closer in proximity to nearby structures.^2,3

Histologically, a schwannoma is encapsulated by the perineurium of the nerve bundle from which it originates (quiz image [top]). The tumor consists of hypercellular (Antoni type A) and hypocellular (Antoni type B) areas. Antoni type A areas consist of tightly packed, spindleshaped cells with elongated wavy nuclei and indistinct cytoplasmic borders. These nuclei tend to align into parallel rows with intervening anuclear zones forming Verocay bodies (quiz image [bottom]).⁴ Verocay bodies are not seen in all schwannomas, and similar formations may be seen in other tumors as well. Solitary circumscribed neuromas also have Verocay bodies, whereas dermatofibromas and leiomyomas have Verocay-like bodies. Antoni type B areas have scattered spindled or ovoid cells in an edematous or myxoid matrix interspersed with inflammatory cells such as lymphocytes and histiocytes. Vessels with thick hyalinized walls are a helpful feature in diagnosis.² Schwann cells of a schwannoma stain diffusely positive with S-100 protein. The capsule stains positively with epithelial membrane antigen due to the presence of perineurial cells.²

The morphologic variants of this entity include conventional (common, solitary), cellular, plexiform, ancient, melanotic, epithelioid, pseudoglandular, neuroblastomalike, and microcystic/reticular schwannomas. There are additional variants that are associated with genetic syndromes, such as multiple cutaneous plexiform schwannomas linked with neurofibromatosis type 2, psammomatous melanotic schwannoma presenting in Carney complex, schwannomatosis, and segmental schwannomatosis (a distinct form of neurofibromatosis characterized by multiple schwannomas localized to one limb). Either presentation may have alteration or deletion of the neurofibromatosis type 2 gene, NF2, on chromosome 22.^2,5

Nodular fasciitis is a benign tumor of fibroblasts and myofibroblasts that usually arises in the subcutaneous tissues. It most commonly occurs in the upper extremities, trunk, head, and neck. It presents as a single, often painful, rapidly growing, subcutaneous nodule. Histologically, lesions mostly are well circumscribed yet unencapsulated, in contrast to schwannomas. They may be hypocellular or hypercellular and are composed of uniform spindle cells with a feathery or fascicular (tissue culture–like) appearance in a loose, myxoid to collagenous stroma. There may be foci of hemorrhage and conspicuous mitoses but not atypical figures (Figure 1). Immunohistochemically, the cells stain positively for smooth muscle actin and negatively for S-100 protein, which sets it apart from a schwannoma. Most cases contain fusion genes, with myosin heavy chain 9 ubiquitin-specific peptidase 6, MYH9-USP6, being the most common fusion product.⁶

Solitary circumscribed neuroma (palisaded encapsulated neuroma) is a benign, usually solitary dermal lesion. It most commonly occurs in middle-aged to elderly adults as a small (<1 cm), firm, flesh-colored to pink papule on the face (ie, cheeks, nose, nasolabial folds) and less commonly in the oral and acral regions and on the eyelids and penis. The lesion usually is unilobular; however, other growth patterns such as plexiform, multilobular, and fungating variants have been identified. Histologically, it is a well-circumscribed nodule with a thin capsule of perineurium that is composed of interlacing bundles of Schwann cells with a characteristic clefting artifact (Figure 2). Cells have wavy dark nuclei with scant cytoplasm that occasionally form palisades or Verocay bodies causing these lesions to be confused with schwannomas. Immunohistochemically, the Schwann cells stain positively with S-100 protein, and the perineurium stains positively with epithelial membrane antigen, Claudin-1, and Glut-1. Neurofilament protein stains axons throughout neuromas, whereas in schwannoma, the expression often is limited to entrapped axons at the periphery of the tumor.⁷

Angioleiomyoma is an uncommon, benign, smooth muscle neoplasm of the skin and subcutaneous tissue that originates from vascular smooth muscle. It most commonly presents in adult females aged 30 to 60 years, with a predilection for the lower limbs. These tumors typically are solitary, slow growing, and less than 2 cm in diameter and may be painful upon compression. Similar to schwannoma, angioleiomyoma is an encapsulated lesion composed of interlacing, uniform, smooth muscle bundles distributed around vessels (Figure 3). Smooth muscle cells have oval- or cigar-shaped nuclei with a small perinuclear vacuole of glycogen. Immunohistochemically, there is strong diffuse staining for smooth muscle actin and h-caldesmon. Recurrence after excision is rare.^2,8

Neurofibroma is a common, mostly sporadic, benign tumor of nerve sheath origin. The solitary type may be localized (well circumscribed, unencapsulated) or diffuse. The presence of multiple, deep, and plexiform lesions is associated with neurofibromatosis type 1 (von Recklinghausen disease) that is caused by germline mutations in the NF1 gene. Histologically, the tumor is composed of Schwann cells, fibroblasts, perineurial cells, and nerve axons within an extracellular myxoid to collagenous matrix (Figure 4). The diffuse type is an ill-defined proliferation that entraps adnexal structures. The plexiform type is defined by multinodular serpentine fascicles. Immunohistochemically, the Schwann cells stain positive for S-100 protein and SOX10 (SRY-Box Transcription Factor 10). Epithelial membrane antigen stains admixed perineurial cells. Neurofilament protein highlights intratumoral axons, which generally are not found throughout schwannomas. Transformation to a malignant peripheral nerve sheath tumor occurs in up to 10% of patients with neurofibromatosis type 1, usually in plexiform neurofibromas, and is characterized by increased cellularity, atypia, mitotic activity, and necrosis.⁹

The Diagnosis: Schwannoma

Schwannoma, also known as neurilemmoma, is a benign encapsulated neoplasm of the peripheral nerve sheath that presents as a subcutaneous nodule.¹ It also may present in the retroperitoneum, mediastinum, and viscera (eg, gastrointestinal tract, bone, upper respiratory tract, lymph nodes). It may occur as multiple lesions when associated with certain syndromes. It usually is an asymptomatic indolent tumor with neurologic symptoms, such as pain and tenderness, in the lesions that are deeper, larger, or closer in proximity to nearby structures.^2,3

Histologically, a schwannoma is encapsulated by the perineurium of the nerve bundle from which it originates (quiz image [top]). The tumor consists of hypercellular (Antoni type A) and hypocellular (Antoni type B) areas. Antoni type A areas consist of tightly packed, spindleshaped cells with elongated wavy nuclei and indistinct cytoplasmic borders. These nuclei tend to align into parallel rows with intervening anuclear zones forming Verocay bodies (quiz image [bottom]).⁴ Verocay bodies are not seen in all schwannomas, and similar formations may be seen in other tumors as well. Solitary circumscribed neuromas also have Verocay bodies, whereas dermatofibromas and leiomyomas have Verocay-like bodies. Antoni type B areas have scattered spindled or ovoid cells in an edematous or myxoid matrix interspersed with inflammatory cells such as lymphocytes and histiocytes. Vessels with thick hyalinized walls are a helpful feature in diagnosis.² Schwann cells of a schwannoma stain diffusely positive with S-100 protein. The capsule stains positively with epithelial membrane antigen due to the presence of perineurial cells.²

The morphologic variants of this entity include conventional (common, solitary), cellular, plexiform, ancient, melanotic, epithelioid, pseudoglandular, neuroblastomalike, and microcystic/reticular schwannomas. There are additional variants that are associated with genetic syndromes, such as multiple cutaneous plexiform schwannomas linked with neurofibromatosis type 2, psammomatous melanotic schwannoma presenting in Carney complex, schwannomatosis, and segmental schwannomatosis (a distinct form of neurofibromatosis characterized by multiple schwannomas localized to one limb). Either presentation may have alteration or deletion of the neurofibromatosis type 2 gene, NF2, on chromosome 22.^2,5

Nodular fasciitis is a benign tumor of fibroblasts and myofibroblasts that usually arises in the subcutaneous tissues. It most commonly occurs in the upper extremities, trunk, head, and neck. It presents as a single, often painful, rapidly growing, subcutaneous nodule. Histologically, lesions mostly are well circumscribed yet unencapsulated, in contrast to schwannomas. They may be hypocellular or hypercellular and are composed of uniform spindle cells with a feathery or fascicular (tissue culture–like) appearance in a loose, myxoid to collagenous stroma. There may be foci of hemorrhage and conspicuous mitoses but not atypical figures (Figure 1). Immunohistochemically, the cells stain positively for smooth muscle actin and negatively for S-100 protein, which sets it apart from a schwannoma. Most cases contain fusion genes, with myosin heavy chain 9 ubiquitin-specific peptidase 6, MYH9-USP6, being the most common fusion product.⁶

Solitary circumscribed neuroma (palisaded encapsulated neuroma) is a benign, usually solitary dermal lesion. It most commonly occurs in middle-aged to elderly adults as a small (<1 cm), firm, flesh-colored to pink papule on the face (ie, cheeks, nose, nasolabial folds) and less commonly in the oral and acral regions and on the eyelids and penis. The lesion usually is unilobular; however, other growth patterns such as plexiform, multilobular, and fungating variants have been identified. Histologically, it is a well-circumscribed nodule with a thin capsule of perineurium that is composed of interlacing bundles of Schwann cells with a characteristic clefting artifact (Figure 2). Cells have wavy dark nuclei with scant cytoplasm that occasionally form palisades or Verocay bodies causing these lesions to be confused with schwannomas. Immunohistochemically, the Schwann cells stain positively with S-100 protein, and the perineurium stains positively with epithelial membrane antigen, Claudin-1, and Glut-1. Neurofilament protein stains axons throughout neuromas, whereas in schwannoma, the expression often is limited to entrapped axons at the periphery of the tumor.⁷

Angioleiomyoma is an uncommon, benign, smooth muscle neoplasm of the skin and subcutaneous tissue that originates from vascular smooth muscle. It most commonly presents in adult females aged 30 to 60 years, with a predilection for the lower limbs. These tumors typically are solitary, slow growing, and less than 2 cm in diameter and may be painful upon compression. Similar to schwannoma, angioleiomyoma is an encapsulated lesion composed of interlacing, uniform, smooth muscle bundles distributed around vessels (Figure 3). Smooth muscle cells have oval- or cigar-shaped nuclei with a small perinuclear vacuole of glycogen. Immunohistochemically, there is strong diffuse staining for smooth muscle actin and h-caldesmon. Recurrence after excision is rare.^2,8

Neurofibroma is a common, mostly sporadic, benign tumor of nerve sheath origin. The solitary type may be localized (well circumscribed, unencapsulated) or diffuse. The presence of multiple, deep, and plexiform lesions is associated with neurofibromatosis type 1 (von Recklinghausen disease) that is caused by germline mutations in the NF1 gene. Histologically, the tumor is composed of Schwann cells, fibroblasts, perineurial cells, and nerve axons within an extracellular myxoid to collagenous matrix (Figure 4). The diffuse type is an ill-defined proliferation that entraps adnexal structures. The plexiform type is defined by multinodular serpentine fascicles. Immunohistochemically, the Schwann cells stain positive for S-100 protein and SOX10 (SRY-Box Transcription Factor 10). Epithelial membrane antigen stains admixed perineurial cells. Neurofilament protein highlights intratumoral axons, which generally are not found throughout schwannomas. Transformation to a malignant peripheral nerve sheath tumor occurs in up to 10% of patients with neurofibromatosis type 1, usually in plexiform neurofibromas, and is characterized by increased cellularity, atypia, mitotic activity, and necrosis.⁹

Opzelura FDA Approved for Atopic Dermatitis Incyte

Corporation announces US Food and Drug Administration (FDA) approval of Opzelura (ruxolitinib) cream 1.5% for the short-term and noncontinuous chronic treatment of mild to moderate atopic dermatitis (AD) in nonimmunocompromised patients 12 years and older whose disease is not adequately controlled with topical prescription therapies or when those therapies are not advisable. Opzelura is formulated with ruxolitinib, a selective Janus kinase (JAK) 1/JAK2 inhibitor, to target key cytokine signals believed to contribute to itch and inflammation. For more information, visit www.opzelurahcp.com/.

Twyneo FDA Approved for Acne Vulgaris

Sol-Gel Technologies, Ltd, announces US Food and Drug Administration (FDA) approval of Twyneo (tretinoin 0.1% /benzoyl peroxide 3%) cream for the treatment of acne vulgaris in adult and pediatric patients 9 years and older. Tretinoin and benzoyl peroxide are widely prescribed separately for acne vulgaris; however, benzoyl peroxide causes degradation of the tretinoin molecule, thereby potentially reducing its effectiveness if used at the same time or combined in the same formulation. The formulation of Twyneo uses silica (silicon dioxide) core shell structures to separately microencapsulate tretinoin crystals and benzoyl peroxide crystals, enabling inclusion of the 2 active ingredients in the cream. For more information, visit www.sol-gel.com.

If you would like your product included in Product News, please email a press release to the Editorial Office at cutis@mdedge.com.

Opzelura FDA Approved for Atopic Dermatitis Incyte

Corporation announces US Food and Drug Administration (FDA) approval of Opzelura (ruxolitinib) cream 1.5% for the short-term and noncontinuous chronic treatment of mild to moderate atopic dermatitis (AD) in nonimmunocompromised patients 12 years and older whose disease is not adequately controlled with topical prescription therapies or when those therapies are not advisable. Opzelura is formulated with ruxolitinib, a selective Janus kinase (JAK) 1/JAK2 inhibitor, to target key cytokine signals believed to contribute to itch and inflammation. For more information, visit www.opzelurahcp.com/.

Twyneo FDA Approved for Acne Vulgaris

Sol-Gel Technologies, Ltd, announces US Food and Drug Administration (FDA) approval of Twyneo (tretinoin 0.1% /benzoyl peroxide 3%) cream for the treatment of acne vulgaris in adult and pediatric patients 9 years and older. Tretinoin and benzoyl peroxide are widely prescribed separately for acne vulgaris; however, benzoyl peroxide causes degradation of the tretinoin molecule, thereby potentially reducing its effectiveness if used at the same time or combined in the same formulation. The formulation of Twyneo uses silica (silicon dioxide) core shell structures to separately microencapsulate tretinoin crystals and benzoyl peroxide crystals, enabling inclusion of the 2 active ingredients in the cream. For more information, visit www.sol-gel.com.

If you would like your product included in Product News, please email a press release to the Editorial Office at cutis@mdedge.com.

Opzelura FDA Approved for Atopic Dermatitis Incyte

Corporation announces US Food and Drug Administration (FDA) approval of Opzelura (ruxolitinib) cream 1.5% for the short-term and noncontinuous chronic treatment of mild to moderate atopic dermatitis (AD) in nonimmunocompromised patients 12 years and older whose disease is not adequately controlled with topical prescription therapies or when those therapies are not advisable. Opzelura is formulated with ruxolitinib, a selective Janus kinase (JAK) 1/JAK2 inhibitor, to target key cytokine signals believed to contribute to itch and inflammation. For more information, visit www.opzelurahcp.com/.

Twyneo FDA Approved for Acne Vulgaris

Sol-Gel Technologies, Ltd, announces US Food and Drug Administration (FDA) approval of Twyneo (tretinoin 0.1% /benzoyl peroxide 3%) cream for the treatment of acne vulgaris in adult and pediatric patients 9 years and older. Tretinoin and benzoyl peroxide are widely prescribed separately for acne vulgaris; however, benzoyl peroxide causes degradation of the tretinoin molecule, thereby potentially reducing its effectiveness if used at the same time or combined in the same formulation. The formulation of Twyneo uses silica (silicon dioxide) core shell structures to separately microencapsulate tretinoin crystals and benzoyl peroxide crystals, enabling inclusion of the 2 active ingredients in the cream. For more information, visit www.sol-gel.com.

If you would like your product included in Product News, please email a press release to the Editorial Office at cutis@mdedge.com.

The COVID-19 pandemic has markedly changed the dermatology residency application process. As medical students head into this application cycle, the impacts of systemic racism and deeply rooted structural barriers continue to be exacerbated for students who identify as an underrepresented minority (URM) in medicine—historically defined as those who self-identify as Hispanic or Latinx; Black or African American; American Indian or Alaska Native; or Native Hawaiian or Pacific Islander. The Association of American Medical Colleges (AAMC) defines URMs as racial and ethnic populations that are underrepresented in medicine relative to their numbers in the general population.¹ Although these groups account for approximately 34% of the population of the United States, they constitute only 11% of the country’s physician workforce.^2,3

Of the total physician workforce in the United States, Black and African American physicians account for 5% of practicing physicians; Hispanic physicians, 5.8%; American Indian and Alaska Native physicians, 0.3%; and Native Hawaiian and Pacific Islander physicians, 0.1%.² In competitive medical specialties, the disproportionality of these numbers compared to our current demographics in the United States as shown above is even more staggering. In 2018, for example, 10% of practicing dermatologists identified as female URM physicians; 6%, as male URM physicians.² In this article, we discuss some of the challenges and considerations for URM students applying to dermatology residency in the era of the COVID-19 pandemic.

Barriers for URM Students in Dermatology

Multiple studies have attempted to identify some of the barriers faced by URM students in medicine that might explain the lack of diversity in competitive specialties. Vasquez and colleagues⁴ identified 4 major factors that play a role in dermatology: lack of equitable resources, lack of support, financial limitations, and the lack of group identity. More than half of URM students surveyed (1) identified lack of support as a barrier and (2) reported having been encouraged to seek a specialty more reflective of their community.⁴

Soliman et al⁵ reported that URM barriers in dermatology extend to include lack of diversity in the field, socioeconomic factors, lack of mentorship, and a negative perception of minority students by residency programs. Dermatology is the second least diverse specialty in medicine after orthopedic surgery, which, in and of itself, might further discourage URM students from applying to dermatology.⁵

With the minimal exposure that URM students have to the field of dermatology, the lack of pipeline programs, and reports that URMs often are encouraged to pursue primary care, the current diversity deficiency in dermatology comes as no surprise. In addition, the substantial disadvantage for URM students is perpetuated by the traditional highly selective process that favors grades, board scores, and honor society status over holistic assessment of the individual student and their unique experiences and potential for contribution.

Looking Beyond Test Scores

The US Medical Licensing Examination (USMLE) traditionally has been used to select dermatology residency applicants, with high cutoff scores often excluding outstanding URM students. Research has suggested that the use of USMLE examination test scores for residency recruitment lacks validity because it has poor predictability of residency performance.⁶ Although the USMLE Step 1 examination is transitioning to pass/fail scoring, applicants for the next cycle will still have a 3-digit numerical score.

We strongly recommend that dermatology programs transition from emphasizing scores of residency candidates to reviewing each candidate holistically. The AAMC defines “holistic review” as a “flexible, individualized way of assessing an applicant’s capabilities, by which balanced consideration is given to experiences, attributes, competencies, and academic or scholarly metrics and, when considered in combination, how the individual might contribute value to the institution’s mission.”⁷ Furthermore, we recommend that dermatology residency programs have multiple faculty members review each application, including a representative of the diversity, inclusion, and equity committee.

In the COVID-19 era, dermatology externship opportunities that would have allowed URM students to work directly with potential residency programs, showcase their abilities, and network have been limited. Virtual residency interviews could make it more challenging to evaluate candidates, especially URM students from less prestigious programs or unusual socioeconomic backgrounds, or with lower board scores. In addition, virtual interviews can more easily become one-dimensional, depriving URM students of the opportunity to gauge their personal fit in a specific dermatology residency program and its community. Questions and concerns of URM students might include: Will I be appropriately supported and mentored? Will my cultural preferences, religion, sexual preference, hairstyle, and beliefs be accepted? Can I advocate for minorities and support antiracism and diversity and inclusion initiatives? To that end, we recommend that dermatology programs continue to host virtual meet-and-greet events for potential students to meet faculty and learn more about the program. In addition, programs should consider having current residents interact virtually with candidates to allow students to better understand the culture of the department and residents’ experiences as trainees in such an environment. For URM students, this is highly important because diversity, inclusion, and antiracism policies and initiatives might not be explicitly available on the institution’s website or residency information page.

Organizations Championing Diversity

Recently, multiple dermatology societies and organizations have been emphasizing the need for diversity and inclusion as well as promoting holistic application review. The American Academy of Dermatology pioneered the Diversity Champion Workshop in 2019 and continues to offer the Diversity Mentorship program, connecting URM students to mentors nationally. The Skin of Color Society offers yearly grants and awards to medical students to develop mentorship and research, and recently hosted webinars to guide medical students and residency programs on diversity and inclusion, residency application and review, and COVID-19 virtual interviews. Other national societies, such as the Student National Medical Association and Latino Medical Student Association, have been promoting workshops and interview mentoring for URM students, including dermatology-specific events. Although it is estimated that more than 90% of medical schools in the United States already perform holistic application review and that such review has been adopted by many dermatology programs nationwide, data regarding dermatology residency programs’ implementation of holistic application review are lacking.⁸

In addition, we encourage continuation of the proposed coordinated interview invite release from the Association of Professors of Dermatology, which was implemented in the 2020-2021 cycle. In light of the recent AAMC letter⁹ on the maldistribution of interview invitations to highest-tier applicants, coordination of interview release dates and other similar initiatives to prevent programs from offering more invites than their available slots and improve transparency about interview days are needed. Furthermore, continuing to offer optional virtual interviews for applicants in future cycles could make the process less cost-prohibitive for many URM students.^4,5

Final Thoughts

Dermatology residency programs must intentionally guard against falling back to traditional standards of assessment as the only means of student evaluation, especially in this virtual era. It is our responsibility to remove artificial barriers that continue to stall progress in diversity, inclusion, equity, and belonging in dermatology.

The COVID-19 pandemic has markedly changed the dermatology residency application process. As medical students head into this application cycle, the impacts of systemic racism and deeply rooted structural barriers continue to be exacerbated for students who identify as an underrepresented minority (URM) in medicine—historically defined as those who self-identify as Hispanic or Latinx; Black or African American; American Indian or Alaska Native; or Native Hawaiian or Pacific Islander. The Association of American Medical Colleges (AAMC) defines URMs as racial and ethnic populations that are underrepresented in medicine relative to their numbers in the general population.¹ Although these groups account for approximately 34% of the population of the United States, they constitute only 11% of the country’s physician workforce.^2,3

Of the total physician workforce in the United States, Black and African American physicians account for 5% of practicing physicians; Hispanic physicians, 5.8%; American Indian and Alaska Native physicians, 0.3%; and Native Hawaiian and Pacific Islander physicians, 0.1%.² In competitive medical specialties, the disproportionality of these numbers compared to our current demographics in the United States as shown above is even more staggering. In 2018, for example, 10% of practicing dermatologists identified as female URM physicians; 6%, as male URM physicians.² In this article, we discuss some of the challenges and considerations for URM students applying to dermatology residency in the era of the COVID-19 pandemic.

Barriers for URM Students in Dermatology

Multiple studies have attempted to identify some of the barriers faced by URM students in medicine that might explain the lack of diversity in competitive specialties. Vasquez and colleagues⁴ identified 4 major factors that play a role in dermatology: lack of equitable resources, lack of support, financial limitations, and the lack of group identity. More than half of URM students surveyed (1) identified lack of support as a barrier and (2) reported having been encouraged to seek a specialty more reflective of their community.⁴

Soliman et al⁵ reported that URM barriers in dermatology extend to include lack of diversity in the field, socioeconomic factors, lack of mentorship, and a negative perception of minority students by residency programs. Dermatology is the second least diverse specialty in medicine after orthopedic surgery, which, in and of itself, might further discourage URM students from applying to dermatology.⁵

With the minimal exposure that URM students have to the field of dermatology, the lack of pipeline programs, and reports that URMs often are encouraged to pursue primary care, the current diversity deficiency in dermatology comes as no surprise. In addition, the substantial disadvantage for URM students is perpetuated by the traditional highly selective process that favors grades, board scores, and honor society status over holistic assessment of the individual student and their unique experiences and potential for contribution.

Looking Beyond Test Scores

The US Medical Licensing Examination (USMLE) traditionally has been used to select dermatology residency applicants, with high cutoff scores often excluding outstanding URM students. Research has suggested that the use of USMLE examination test scores for residency recruitment lacks validity because it has poor predictability of residency performance.⁶ Although the USMLE Step 1 examination is transitioning to pass/fail scoring, applicants for the next cycle will still have a 3-digit numerical score.

We strongly recommend that dermatology programs transition from emphasizing scores of residency candidates to reviewing each candidate holistically. The AAMC defines “holistic review” as a “flexible, individualized way of assessing an applicant’s capabilities, by which balanced consideration is given to experiences, attributes, competencies, and academic or scholarly metrics and, when considered in combination, how the individual might contribute value to the institution’s mission.”⁷ Furthermore, we recommend that dermatology residency programs have multiple faculty members review each application, including a representative of the diversity, inclusion, and equity committee.

In the COVID-19 era, dermatology externship opportunities that would have allowed URM students to work directly with potential residency programs, showcase their abilities, and network have been limited. Virtual residency interviews could make it more challenging to evaluate candidates, especially URM students from less prestigious programs or unusual socioeconomic backgrounds, or with lower board scores. In addition, virtual interviews can more easily become one-dimensional, depriving URM students of the opportunity to gauge their personal fit in a specific dermatology residency program and its community. Questions and concerns of URM students might include: Will I be appropriately supported and mentored? Will my cultural preferences, religion, sexual preference, hairstyle, and beliefs be accepted? Can I advocate for minorities and support antiracism and diversity and inclusion initiatives? To that end, we recommend that dermatology programs continue to host virtual meet-and-greet events for potential students to meet faculty and learn more about the program. In addition, programs should consider having current residents interact virtually with candidates to allow students to better understand the culture of the department and residents’ experiences as trainees in such an environment. For URM students, this is highly important because diversity, inclusion, and antiracism policies and initiatives might not be explicitly available on the institution’s website or residency information page.

Organizations Championing Diversity

Recently, multiple dermatology societies and organizations have been emphasizing the need for diversity and inclusion as well as promoting holistic application review. The American Academy of Dermatology pioneered the Diversity Champion Workshop in 2019 and continues to offer the Diversity Mentorship program, connecting URM students to mentors nationally. The Skin of Color Society offers yearly grants and awards to medical students to develop mentorship and research, and recently hosted webinars to guide medical students and residency programs on diversity and inclusion, residency application and review, and COVID-19 virtual interviews. Other national societies, such as the Student National Medical Association and Latino Medical Student Association, have been promoting workshops and interview mentoring for URM students, including dermatology-specific events. Although it is estimated that more than 90% of medical schools in the United States already perform holistic application review and that such review has been adopted by many dermatology programs nationwide, data regarding dermatology residency programs’ implementation of holistic application review are lacking.⁸

In addition, we encourage continuation of the proposed coordinated interview invite release from the Association of Professors of Dermatology, which was implemented in the 2020-2021 cycle. In light of the recent AAMC letter⁹ on the maldistribution of interview invitations to highest-tier applicants, coordination of interview release dates and other similar initiatives to prevent programs from offering more invites than their available slots and improve transparency about interview days are needed. Furthermore, continuing to offer optional virtual interviews for applicants in future cycles could make the process less cost-prohibitive for many URM students.^4,5

Final Thoughts

Dermatology residency programs must intentionally guard against falling back to traditional standards of assessment as the only means of student evaluation, especially in this virtual era. It is our responsibility to remove artificial barriers that continue to stall progress in diversity, inclusion, equity, and belonging in dermatology.

The COVID-19 pandemic has markedly changed the dermatology residency application process. As medical students head into this application cycle, the impacts of systemic racism and deeply rooted structural barriers continue to be exacerbated for students who identify as an underrepresented minority (URM) in medicine—historically defined as those who self-identify as Hispanic or Latinx; Black or African American; American Indian or Alaska Native; or Native Hawaiian or Pacific Islander. The Association of American Medical Colleges (AAMC) defines URMs as racial and ethnic populations that are underrepresented in medicine relative to their numbers in the general population.¹ Although these groups account for approximately 34% of the population of the United States, they constitute only 11% of the country’s physician workforce.^2,3

Of the total physician workforce in the United States, Black and African American physicians account for 5% of practicing physicians; Hispanic physicians, 5.8%; American Indian and Alaska Native physicians, 0.3%; and Native Hawaiian and Pacific Islander physicians, 0.1%.² In competitive medical specialties, the disproportionality of these numbers compared to our current demographics in the United States as shown above is even more staggering. In 2018, for example, 10% of practicing dermatologists identified as female URM physicians; 6%, as male URM physicians.² In this article, we discuss some of the challenges and considerations for URM students applying to dermatology residency in the era of the COVID-19 pandemic.

Barriers for URM Students in Dermatology

Multiple studies have attempted to identify some of the barriers faced by URM students in medicine that might explain the lack of diversity in competitive specialties. Vasquez and colleagues⁴ identified 4 major factors that play a role in dermatology: lack of equitable resources, lack of support, financial limitations, and the lack of group identity. More than half of URM students surveyed (1) identified lack of support as a barrier and (2) reported having been encouraged to seek a specialty more reflective of their community.⁴

Soliman et al⁵ reported that URM barriers in dermatology extend to include lack of diversity in the field, socioeconomic factors, lack of mentorship, and a negative perception of minority students by residency programs. Dermatology is the second least diverse specialty in medicine after orthopedic surgery, which, in and of itself, might further discourage URM students from applying to dermatology.⁵

With the minimal exposure that URM students have to the field of dermatology, the lack of pipeline programs, and reports that URMs often are encouraged to pursue primary care, the current diversity deficiency in dermatology comes as no surprise. In addition, the substantial disadvantage for URM students is perpetuated by the traditional highly selective process that favors grades, board scores, and honor society status over holistic assessment of the individual student and their unique experiences and potential for contribution.

Looking Beyond Test Scores

The US Medical Licensing Examination (USMLE) traditionally has been used to select dermatology residency applicants, with high cutoff scores often excluding outstanding URM students. Research has suggested that the use of USMLE examination test scores for residency recruitment lacks validity because it has poor predictability of residency performance.⁶ Although the USMLE Step 1 examination is transitioning to pass/fail scoring, applicants for the next cycle will still have a 3-digit numerical score.

We strongly recommend that dermatology programs transition from emphasizing scores of residency candidates to reviewing each candidate holistically. The AAMC defines “holistic review” as a “flexible, individualized way of assessing an applicant’s capabilities, by which balanced consideration is given to experiences, attributes, competencies, and academic or scholarly metrics and, when considered in combination, how the individual might contribute value to the institution’s mission.”⁷ Furthermore, we recommend that dermatology residency programs have multiple faculty members review each application, including a representative of the diversity, inclusion, and equity committee.

In the COVID-19 era, dermatology externship opportunities that would have allowed URM students to work directly with potential residency programs, showcase their abilities, and network have been limited. Virtual residency interviews could make it more challenging to evaluate candidates, especially URM students from less prestigious programs or unusual socioeconomic backgrounds, or with lower board scores. In addition, virtual interviews can more easily become one-dimensional, depriving URM students of the opportunity to gauge their personal fit in a specific dermatology residency program and its community. Questions and concerns of URM students might include: Will I be appropriately supported and mentored? Will my cultural preferences, religion, sexual preference, hairstyle, and beliefs be accepted? Can I advocate for minorities and support antiracism and diversity and inclusion initiatives? To that end, we recommend that dermatology programs continue to host virtual meet-and-greet events for potential students to meet faculty and learn more about the program. In addition, programs should consider having current residents interact virtually with candidates to allow students to better understand the culture of the department and residents’ experiences as trainees in such an environment. For URM students, this is highly important because diversity, inclusion, and antiracism policies and initiatives might not be explicitly available on the institution’s website or residency information page.

Organizations Championing Diversity

Recently, multiple dermatology societies and organizations have been emphasizing the need for diversity and inclusion as well as promoting holistic application review. The American Academy of Dermatology pioneered the Diversity Champion Workshop in 2019 and continues to offer the Diversity Mentorship program, connecting URM students to mentors nationally. The Skin of Color Society offers yearly grants and awards to medical students to develop mentorship and research, and recently hosted webinars to guide medical students and residency programs on diversity and inclusion, residency application and review, and COVID-19 virtual interviews. Other national societies, such as the Student National Medical Association and Latino Medical Student Association, have been promoting workshops and interview mentoring for URM students, including dermatology-specific events. Although it is estimated that more than 90% of medical schools in the United States already perform holistic application review and that such review has been adopted by many dermatology programs nationwide, data regarding dermatology residency programs’ implementation of holistic application review are lacking.⁸

In addition, we encourage continuation of the proposed coordinated interview invite release from the Association of Professors of Dermatology, which was implemented in the 2020-2021 cycle. In light of the recent AAMC letter⁹ on the maldistribution of interview invitations to highest-tier applicants, coordination of interview release dates and other similar initiatives to prevent programs from offering more invites than their available slots and improve transparency about interview days are needed. Furthermore, continuing to offer optional virtual interviews for applicants in future cycles could make the process less cost-prohibitive for many URM students.^4,5

Final Thoughts

Dermatology residency programs must intentionally guard against falling back to traditional standards of assessment as the only means of student evaluation, especially in this virtual era. It is our responsibility to remove artificial barriers that continue to stall progress in diversity, inclusion, equity, and belonging in dermatology.

To the Editor:

The tumor necrosis factor α inhibitor adalimumab is the only US Food and Drug Administration–approved treatment of hidradenitis suppurativa (HS). Although 50.6% of patients fulfilled Hidradenitis Suppurativa Clinical Response criteria with adalimumab at 12 weeks, many responders were not satisfied with their disease control, and secondary loss of Hidradenitis Suppurativa Clinical Response fulfillment occurred in 15.9% of patients within approximately 3 years.¹ Without other US Food and Drug Administration–approved HS treatments, some dermatologists have combined adalimumab with methotrexate (MTX) and/or mycophenolate mofetil (MMF) to attempt to increase the duration of satisfactory disease control while on adalimumab. Combining tumor necrosis factor α inhibitors with oral immunosuppressants is a well-established approach in psoriasis, psoriatic arthritis, and inflammatory bowel disease; however, to the best of our knowledge, this approach has not been studied for HS.^2,3

To assess whether there is a role for combining adalimumab with MTX and/or MMF in the treatment of HS, we performed a single-institution retrospective chart review at the University of Connecticut Department of Dermatology to determine whether patients receiving combination therapy stayed on adalimumab longer than those who received adalimumab monotherapy. All patients receiving adalimumab for the treatment of HS with at least 1 follow-up visit 3 or more months after treatment initiation were included. Duration of treatment with adalimumab was defined as the length of time between initiation and termination of adalimumab, regardless of flares, adverse events, or addition of adjuvant therapy that occurred during this time span. Because standardized rating scales measuring the severity of HS at this time are not recorded routinely at our institution, treatment duration with adalimumab was used as a surrogate for measuring therapeutic success. Additionally, treatment duration is a meaningful end point, as patients with HS may require indefinite treatment. Patients were eligible for inclusion if they were receiving adalimumab for the treatment of HS. Patients were excluded if they were lost to follow-up or had received adalimumab for less than 6 months, as data suggest that biologics do not reach peak effect for up to 6 months in HS.⁴

We identified 116 eligible patients with HS, 32 of whom received combination therapy. Five patients received 40 mg of adalimumab every other week, and 111 patients received 40 mg of adalimumab each week. Patients receiving oral immunosuppressants were more likely to be male and as likely to be biologic naïve compared to patients on monotherapy (Table). The average weekly dose of MTX was 14.63 mg, and the average daily dose of MMF was 1000 mg. The average number of days between starting adalimumab and starting an oral immunosuppressant was 114.5 (SD, 217; median, 0) days. Reasons for discontinuation of adalimumab included insufficient response, noncompliance, dislike of injections, adverse events, fear of adverse events, other medical issues unrelated to HS, and insurance coverage issues. Patients who ended treatment with adalimumab owing to insurance coverage issues were still included in our study because insurance coverage remains a major determinant of treatment choice in HS and is relevant to the dynamics of medical decision-making.

Statistical analysis was conducted on all patients inclusive of any reason for discontinuation to avoid bias in the calculation of treatment duration. Cox regression analysis was conducted for all independent variables and was noncontributory. Kaplan-Meier methodology was used to assess the duration of treatment of adalimumab with and without concomitant oral immunosuppressants, and quartile survival times were calculated. Quartile survival time is the time point after adalimumab initiation at which 25% of patients have discontinued adalimumab. We chose quartile survival time instead of average treatment duration to adequately power this study, given our small patient pool.

Although patients receiving adalimumab with oral immunosuppressants had a longer quartile treatment duration (450 days; 95% CI, 185-1800) than the group without oral immunosuppressants (360 days; 95% CI, 200-700), neither MTX nor MMF was shown to significantly prolong duration of therapy with adalimumab (log-rank test: P=.12). Additionally, patients receiving combination therapy were just as likely to discontinue adalimumab as those on monotherapy (χ² test: P=.93). Patients who took both MTX and MMF at different times did show a statistically significant increase in adalimumab quartile treatment duration (1710 days; 95% CI, 1620 [upper limit not calculable]), but this is likely because these patients were kept on adalimumab while trialing adjunctive medications.

The results of our study indicate that MTX and MMF do not prolong duration of adalimumab therapy, which suggests that adalimumab combination therapy with MTX and MMF may not improve HS more than adalimumab alone, and/or partial responders to adalimumab monotherapy are unlikely to be converted to satisfactory responders with the addition of oral immunosuppressants. Limitations of our study include that it was retrospective, used treatment duration as a surrogate for objective efficacy measures, and relied on a single-institution data source. Additionally, owing to our small sample size, we were unable to account for certain potential confounders, including patient weight and insurance status. Future controlled prospective studies using objective end points are needed to further elucidate whether oral immunosuppressants have a role as an adjunct in the treatment of HS.

To the Editor:

The tumor necrosis factor α inhibitor adalimumab is the only US Food and Drug Administration–approved treatment of hidradenitis suppurativa (HS). Although 50.6% of patients fulfilled Hidradenitis Suppurativa Clinical Response criteria with adalimumab at 12 weeks, many responders were not satisfied with their disease control, and secondary loss of Hidradenitis Suppurativa Clinical Response fulfillment occurred in 15.9% of patients within approximately 3 years.¹ Without other US Food and Drug Administration–approved HS treatments, some dermatologists have combined adalimumab with methotrexate (MTX) and/or mycophenolate mofetil (MMF) to attempt to increase the duration of satisfactory disease control while on adalimumab. Combining tumor necrosis factor α inhibitors with oral immunosuppressants is a well-established approach in psoriasis, psoriatic arthritis, and inflammatory bowel disease; however, to the best of our knowledge, this approach has not been studied for HS.^2,3

To assess whether there is a role for combining adalimumab with MTX and/or MMF in the treatment of HS, we performed a single-institution retrospective chart review at the University of Connecticut Department of Dermatology to determine whether patients receiving combination therapy stayed on adalimumab longer than those who received adalimumab monotherapy. All patients receiving adalimumab for the treatment of HS with at least 1 follow-up visit 3 or more months after treatment initiation were included. Duration of treatment with adalimumab was defined as the length of time between initiation and termination of adalimumab, regardless of flares, adverse events, or addition of adjuvant therapy that occurred during this time span. Because standardized rating scales measuring the severity of HS at this time are not recorded routinely at our institution, treatment duration with adalimumab was used as a surrogate for measuring therapeutic success. Additionally, treatment duration is a meaningful end point, as patients with HS may require indefinite treatment. Patients were eligible for inclusion if they were receiving adalimumab for the treatment of HS. Patients were excluded if they were lost to follow-up or had received adalimumab for less than 6 months, as data suggest that biologics do not reach peak effect for up to 6 months in HS.⁴

We identified 116 eligible patients with HS, 32 of whom received combination therapy. Five patients received 40 mg of adalimumab every other week, and 111 patients received 40 mg of adalimumab each week. Patients receiving oral immunosuppressants were more likely to be male and as likely to be biologic naïve compared to patients on monotherapy (Table). The average weekly dose of MTX was 14.63 mg, and the average daily dose of MMF was 1000 mg. The average number of days between starting adalimumab and starting an oral immunosuppressant was 114.5 (SD, 217; median, 0) days. Reasons for discontinuation of adalimumab included insufficient response, noncompliance, dislike of injections, adverse events, fear of adverse events, other medical issues unrelated to HS, and insurance coverage issues. Patients who ended treatment with adalimumab owing to insurance coverage issues were still included in our study because insurance coverage remains a major determinant of treatment choice in HS and is relevant to the dynamics of medical decision-making.

Statistical analysis was conducted on all patients inclusive of any reason for discontinuation to avoid bias in the calculation of treatment duration. Cox regression analysis was conducted for all independent variables and was noncontributory. Kaplan-Meier methodology was used to assess the duration of treatment of adalimumab with and without concomitant oral immunosuppressants, and quartile survival times were calculated. Quartile survival time is the time point after adalimumab initiation at which 25% of patients have discontinued adalimumab. We chose quartile survival time instead of average treatment duration to adequately power this study, given our small patient pool.

Although patients receiving adalimumab with oral immunosuppressants had a longer quartile treatment duration (450 days; 95% CI, 185-1800) than the group without oral immunosuppressants (360 days; 95% CI, 200-700), neither MTX nor MMF was shown to significantly prolong duration of therapy with adalimumab (log-rank test: P=.12). Additionally, patients receiving combination therapy were just as likely to discontinue adalimumab as those on monotherapy (χ² test: P=.93). Patients who took both MTX and MMF at different times did show a statistically significant increase in adalimumab quartile treatment duration (1710 days; 95% CI, 1620 [upper limit not calculable]), but this is likely because these patients were kept on adalimumab while trialing adjunctive medications.

The results of our study indicate that MTX and MMF do not prolong duration of adalimumab therapy, which suggests that adalimumab combination therapy with MTX and MMF may not improve HS more than adalimumab alone, and/or partial responders to adalimumab monotherapy are unlikely to be converted to satisfactory responders with the addition of oral immunosuppressants. Limitations of our study include that it was retrospective, used treatment duration as a surrogate for objective efficacy measures, and relied on a single-institution data source. Additionally, owing to our small sample size, we were unable to account for certain potential confounders, including patient weight and insurance status. Future controlled prospective studies using objective end points are needed to further elucidate whether oral immunosuppressants have a role as an adjunct in the treatment of HS.

To the Editor:

The tumor necrosis factor α inhibitor adalimumab is the only US Food and Drug Administration–approved treatment of hidradenitis suppurativa (HS). Although 50.6% of patients fulfilled Hidradenitis Suppurativa Clinical Response criteria with adalimumab at 12 weeks, many responders were not satisfied with their disease control, and secondary loss of Hidradenitis Suppurativa Clinical Response fulfillment occurred in 15.9% of patients within approximately 3 years.¹ Without other US Food and Drug Administration–approved HS treatments, some dermatologists have combined adalimumab with methotrexate (MTX) and/or mycophenolate mofetil (MMF) to attempt to increase the duration of satisfactory disease control while on adalimumab. Combining tumor necrosis factor α inhibitors with oral immunosuppressants is a well-established approach in psoriasis, psoriatic arthritis, and inflammatory bowel disease; however, to the best of our knowledge, this approach has not been studied for HS.^2,3

To assess whether there is a role for combining adalimumab with MTX and/or MMF in the treatment of HS, we performed a single-institution retrospective chart review at the University of Connecticut Department of Dermatology to determine whether patients receiving combination therapy stayed on adalimumab longer than those who received adalimumab monotherapy. All patients receiving adalimumab for the treatment of HS with at least 1 follow-up visit 3 or more months after treatment initiation were included. Duration of treatment with adalimumab was defined as the length of time between initiation and termination of adalimumab, regardless of flares, adverse events, or addition of adjuvant therapy that occurred during this time span. Because standardized rating scales measuring the severity of HS at this time are not recorded routinely at our institution, treatment duration with adalimumab was used as a surrogate for measuring therapeutic success. Additionally, treatment duration is a meaningful end point, as patients with HS may require indefinite treatment. Patients were eligible for inclusion if they were receiving adalimumab for the treatment of HS. Patients were excluded if they were lost to follow-up or had received adalimumab for less than 6 months, as data suggest that biologics do not reach peak effect for up to 6 months in HS.⁴

We identified 116 eligible patients with HS, 32 of whom received combination therapy. Five patients received 40 mg of adalimumab every other week, and 111 patients received 40 mg of adalimumab each week. Patients receiving oral immunosuppressants were more likely to be male and as likely to be biologic naïve compared to patients on monotherapy (Table). The average weekly dose of MTX was 14.63 mg, and the average daily dose of MMF was 1000 mg. The average number of days between starting adalimumab and starting an oral immunosuppressant was 114.5 (SD, 217; median, 0) days. Reasons for discontinuation of adalimumab included insufficient response, noncompliance, dislike of injections, adverse events, fear of adverse events, other medical issues unrelated to HS, and insurance coverage issues. Patients who ended treatment with adalimumab owing to insurance coverage issues were still included in our study because insurance coverage remains a major determinant of treatment choice in HS and is relevant to the dynamics of medical decision-making.

Statistical analysis was conducted on all patients inclusive of any reason for discontinuation to avoid bias in the calculation of treatment duration. Cox regression analysis was conducted for all independent variables and was noncontributory. Kaplan-Meier methodology was used to assess the duration of treatment of adalimumab with and without concomitant oral immunosuppressants, and quartile survival times were calculated. Quartile survival time is the time point after adalimumab initiation at which 25% of patients have discontinued adalimumab. We chose quartile survival time instead of average treatment duration to adequately power this study, given our small patient pool.

Although patients receiving adalimumab with oral immunosuppressants had a longer quartile treatment duration (450 days; 95% CI, 185-1800) than the group without oral immunosuppressants (360 days; 95% CI, 200-700), neither MTX nor MMF was shown to significantly prolong duration of therapy with adalimumab (log-rank test: P=.12). Additionally, patients receiving combination therapy were just as likely to discontinue adalimumab as those on monotherapy (χ² test: P=.93). Patients who took both MTX and MMF at different times did show a statistically significant increase in adalimumab quartile treatment duration (1710 days; 95% CI, 1620 [upper limit not calculable]), but this is likely because these patients were kept on adalimumab while trialing adjunctive medications.

The results of our study indicate that MTX and MMF do not prolong duration of adalimumab therapy, which suggests that adalimumab combination therapy with MTX and MMF may not improve HS more than adalimumab alone, and/or partial responders to adalimumab monotherapy are unlikely to be converted to satisfactory responders with the addition of oral immunosuppressants. Limitations of our study include that it was retrospective, used treatment duration as a surrogate for objective efficacy measures, and relied on a single-institution data source. Additionally, owing to our small sample size, we were unable to account for certain potential confounders, including patient weight and insurance status. Future controlled prospective studies using objective end points are needed to further elucidate whether oral immunosuppressants have a role as an adjunct in the treatment of HS.

Practice Gap

The Sarcoptes scabiei mite is a microscopic organism that causes scabies in the human host. The scabies mite is highly transmissible, making scabies a common disease in heavily populated areas. The mite survives by burrowing into the epidermis, where it feeds, lays eggs, and defecates.¹

The rash in the host represents an allergic reaction to the body of the scabies mite, producing symptoms such as intense itching, rash, and erosions of the skin. The scabies rash tends to occur in warm and occluded areas of the body such as the hands, axillae, groin, buttocks, and feet.^1,2

Delaying treatment of scabies can be hazardous because of the risk of rapid spread from one person to another. This rapid spread can be debilitating in specific populations, such as the immunocompromised, elderly, and disabled.

Mineral oil preparation is the classic method used to identify scabies (Figure 1). This method relies on obtaining mites by applying mineral oil to the skin and using a 15-mm blade to scrape off layers of the affected skin. The scraped material is spread onto a microscope slide with mineral oil, a coverslip is applied, and the specimen is analyzed by direct microscopy. This method proves only as effective as knowing where the few mites are located.

At any time, only 10 to 12 mites live on a human host.³ Therefore, it can be challenging to obtain a mite for diagnosis because the location of the skin mites may be unknown. Dermoscopy can be used to locate burrows and other signs of S scabiei. With a dermatoscope, the scabies mite can be identified by the so-called delta-wing jet sign.⁴

However, dermoscopy is not always successful because extensive hemorrhagic crusting and erosions of the skin secondary to constant scratching can obscure the appearance of burrows and mites. Because patients are constantly scratching areas of irritation, it is possible that S scabiei can be located under the fingernail of the dominant hand.

The Technique

To address this practice gap, a mineral oil scabies preparation can be performed by scraping under the fingernail plate at the level of the hyponychium. Mites might accumulate underneath the fingernails of the dominant hand when patients scratch the area of the skin where S scabiei mites are burrowing and reproducing.

A convenient and painless way to obtain a mineral oil scabies preparation from under the fingernail is to use the tip of a disposable hyfrecator, readily available in most dermatology practices for use in electrosurgery (Figure 2). Using the blunt end of the hyfrecator tip for the mineral oil preparation would be done without attachment to the full apparatus.

The hyponychium of the fingernail is prepared with mineral oil, which aids in collecting and suspending the material obtained from under the nail plate. Using the blunt end of the hyfrecator tip, material from underneath the fingernail is removed using a gentle sweeping motion (Figure 3). The specimen is then analyzed under the microscope similar to a routine mineral oil scabies preparation. This method can be utilized by health care providers for easy and painless diagnosis of scabies.

Practice Implications

Use of a blunt hyfrecator tip to extract S scabiei from underneath the fingernail plate can be used for efficient diagnosis of scabies. This technique can be implemented in any clinic where blunt-tip hyfrecator electrodes are available. Using a gentle sweeping motion, the blunt-tip hyfrecator allows the provider to extract material from under the fingernail for diagnosis. The material obtained is used to prepare a mineral oil scabies preparation for direct microscopic analysis.

This technique can diagnose scabies efficiently, and treatment can be initiated promptly. Use of a disposable blunt-tip hyfrecator for scabies extraction is a novel technique that can be added to the armamentarium of tools to diagnose scabies, which includes traditional mineral oil preparation and dermoscopy.

Practice Gap

The Sarcoptes scabiei mite is a microscopic organism that causes scabies in the human host. The scabies mite is highly transmissible, making scabies a common disease in heavily populated areas. The mite survives by burrowing into the epidermis, where it feeds, lays eggs, and defecates.¹

The rash in the host represents an allergic reaction to the body of the scabies mite, producing symptoms such as intense itching, rash, and erosions of the skin. The scabies rash tends to occur in warm and occluded areas of the body such as the hands, axillae, groin, buttocks, and feet.^1,2

Delaying treatment of scabies can be hazardous because of the risk of rapid spread from one person to another. This rapid spread can be debilitating in specific populations, such as the immunocompromised, elderly, and disabled.

Mineral oil preparation is the classic method used to identify scabies (Figure 1). This method relies on obtaining mites by applying mineral oil to the skin and using a 15-mm blade to scrape off layers of the affected skin. The scraped material is spread onto a microscope slide with mineral oil, a coverslip is applied, and the specimen is analyzed by direct microscopy. This method proves only as effective as knowing where the few mites are located.

At any time, only 10 to 12 mites live on a human host.³ Therefore, it can be challenging to obtain a mite for diagnosis because the location of the skin mites may be unknown. Dermoscopy can be used to locate burrows and other signs of S scabiei. With a dermatoscope, the scabies mite can be identified by the so-called delta-wing jet sign.⁴

However, dermoscopy is not always successful because extensive hemorrhagic crusting and erosions of the skin secondary to constant scratching can obscure the appearance of burrows and mites. Because patients are constantly scratching areas of irritation, it is possible that S scabiei can be located under the fingernail of the dominant hand.

The Technique

To address this practice gap, a mineral oil scabies preparation can be performed by scraping under the fingernail plate at the level of the hyponychium. Mites might accumulate underneath the fingernails of the dominant hand when patients scratch the area of the skin where S scabiei mites are burrowing and reproducing.

A convenient and painless way to obtain a mineral oil scabies preparation from under the fingernail is to use the tip of a disposable hyfrecator, readily available in most dermatology practices for use in electrosurgery (Figure 2). Using the blunt end of the hyfrecator tip for the mineral oil preparation would be done without attachment to the full apparatus.

The hyponychium of the fingernail is prepared with mineral oil, which aids in collecting and suspending the material obtained from under the nail plate. Using the blunt end of the hyfrecator tip, material from underneath the fingernail is removed using a gentle sweeping motion (Figure 3). The specimen is then analyzed under the microscope similar to a routine mineral oil scabies preparation. This method can be utilized by health care providers for easy and painless diagnosis of scabies.

Practice Implications

Use of a blunt hyfrecator tip to extract S scabiei from underneath the fingernail plate can be used for efficient diagnosis of scabies. This technique can be implemented in any clinic where blunt-tip hyfrecator electrodes are available. Using a gentle sweeping motion, the blunt-tip hyfrecator allows the provider to extract material from under the fingernail for diagnosis. The material obtained is used to prepare a mineral oil scabies preparation for direct microscopic analysis.

This technique can diagnose scabies efficiently, and treatment can be initiated promptly. Use of a disposable blunt-tip hyfrecator for scabies extraction is a novel technique that can be added to the armamentarium of tools to diagnose scabies, which includes traditional mineral oil preparation and dermoscopy.

Practice Gap

The Sarcoptes scabiei mite is a microscopic organism that causes scabies in the human host. The scabies mite is highly transmissible, making scabies a common disease in heavily populated areas. The mite survives by burrowing into the epidermis, where it feeds, lays eggs, and defecates.¹

The rash in the host represents an allergic reaction to the body of the scabies mite, producing symptoms such as intense itching, rash, and erosions of the skin. The scabies rash tends to occur in warm and occluded areas of the body such as the hands, axillae, groin, buttocks, and feet.^1,2

Delaying treatment of scabies can be hazardous because of the risk of rapid spread from one person to another. This rapid spread can be debilitating in specific populations, such as the immunocompromised, elderly, and disabled.

Mineral oil preparation is the classic method used to identify scabies (Figure 1). This method relies on obtaining mites by applying mineral oil to the skin and using a 15-mm blade to scrape off layers of the affected skin. The scraped material is spread onto a microscope slide with mineral oil, a coverslip is applied, and the specimen is analyzed by direct microscopy. This method proves only as effective as knowing where the few mites are located.

At any time, only 10 to 12 mites live on a human host.³ Therefore, it can be challenging to obtain a mite for diagnosis because the location of the skin mites may be unknown. Dermoscopy can be used to locate burrows and other signs of S scabiei. With a dermatoscope, the scabies mite can be identified by the so-called delta-wing jet sign.⁴

However, dermoscopy is not always successful because extensive hemorrhagic crusting and erosions of the skin secondary to constant scratching can obscure the appearance of burrows and mites. Because patients are constantly scratching areas of irritation, it is possible that S scabiei can be located under the fingernail of the dominant hand.

The Technique

To address this practice gap, a mineral oil scabies preparation can be performed by scraping under the fingernail plate at the level of the hyponychium. Mites might accumulate underneath the fingernails of the dominant hand when patients scratch the area of the skin where S scabiei mites are burrowing and reproducing.

A convenient and painless way to obtain a mineral oil scabies preparation from under the fingernail is to use the tip of a disposable hyfrecator, readily available in most dermatology practices for use in electrosurgery (Figure 2). Using the blunt end of the hyfrecator tip for the mineral oil preparation would be done without attachment to the full apparatus.

The hyponychium of the fingernail is prepared with mineral oil, which aids in collecting and suspending the material obtained from under the nail plate. Using the blunt end of the hyfrecator tip, material from underneath the fingernail is removed using a gentle sweeping motion (Figure 3). The specimen is then analyzed under the microscope similar to a routine mineral oil scabies preparation. This method can be utilized by health care providers for easy and painless diagnosis of scabies.

Practice Implications

Use of a blunt hyfrecator tip to extract S scabiei from underneath the fingernail plate can be used for efficient diagnosis of scabies. This technique can be implemented in any clinic where blunt-tip hyfrecator electrodes are available. Using a gentle sweeping motion, the blunt-tip hyfrecator allows the provider to extract material from under the fingernail for diagnosis. The material obtained is used to prepare a mineral oil scabies preparation for direct microscopic analysis.

This technique can diagnose scabies efficiently, and treatment can be initiated promptly. Use of a disposable blunt-tip hyfrecator for scabies extraction is a novel technique that can be added to the armamentarium of tools to diagnose scabies, which includes traditional mineral oil preparation and dermoscopy.

More than half a million individuals are without housing (NWH) on any given night in the United States, as estimated by the US Department of Housing and Urban Development. ¹ Lack of hygiene, increased risk of infection and infestation due to living conditions, and barriers to health care put these individuals at increased risk for disease. ² Skin disease, including fungal infection and acne, are within the top 10 most prevalent diseases worldwide and can cause major psychologic impairment, yet dermatologic concerns and clinical outcomes in NWH patients have not been well characterized. ^2-5 Further, because this vulnerable demographic tends to be underinsured, they frequently present to the emergency department (ED) for management of disease. ^1,6 Survey of common concerns in NWH patients is of utility to consulting dermatologists and nondermatologist providers in the ED, who can familiarize themselves with management of diseases they are more likely to encounter. Few studies examine dermatologic conditions in the ED, and a thorough literature review indicates none have included homelessness as a variable. ^6,7 Additionally, comparison with a matched control group of patients with housing (WH) is limited. ^5,8 We present one of the largest comparisons of cutaneous disease in NWH vs WH patients in a single hospital system to elucidate the types of cutaneous disease that motivate patients to seek care, the location of skin disease, and differences in clinical care.

Methods

A retrospective medical record review of patients seen for an inclusive list of dermatologic diagnoses in the ED or while admitted at University Medical Center New Orleans, Louisiana (UMC), between January 1, 2018, and April 21, 2020, was conducted. This study was qualified as exempt from the institutional review board by Louisiana State University because it proposed zero risk to the patients and remained completely anonymous. Eight hundred forty-two total medical records were reviewed (NWH, 421; WH, 421)(Table 1). Patients with housing were matched based on self-identified race and ethnicity, sex, and age. Disease categories were constructed based on fundamental pathophysiology adapted from Dermatology⁹: infectious, noninfectious inflammatory, neoplasm, trauma and wounds, drug-related eruptions, vascular, pruritic, pigmented, bullous, neuropsychiatric, and other. Other included unspecified eruptions as well as miscellaneous lesions such as calluses. The current chief concern, anatomic location, and configuration were recorded, as well as biopsied lesions and outpatient referrals or inpatient consultations to dermatology or other specialties, including wound care, infectious disease, podiatry, and surgery. χ² analysis was used to analyze significance of cutaneous categories, body location, and referrals. Groups smaller than 5 defaulted to the Fisher exact test.

Results

The total diagnoses (including both chief concerns and secondary diagnoses) are shown in Table 2. Chief concerns were more frequently cutaneous or dermatologic for WH (NWH, 209; WH, 307; P<.001). In both groups, cutaneous infectious etiologies were more likely to be a patient’s presenting chief concern (58% NWH, P=.002; 42% WH, P<.001). Noninfectious inflammatory etiologies and pigmented lesions were more likely to be secondary diagnoses with an unrelated noncutaneous concern; noninfectious inflammatory etiologies were only 16% of the total cutaneous chief concerns (11% NWH, P=.04; 20% WH, P=.03), and no pigmented lesions were chief concerns.

Infection was the most common chief concern, though NWH patients presented with significantly more infectious concerns (NWH, 212; WH, 150; P<.001), particularly infestations (NWH, 33; WH, 8; P<.001) and bacterial etiologies (NWH, 127; WH, 100; P=.04). The majority of bacterial etiologies were either an abscess or cellulitis (NWH, 106; WH, 83), though infected chronic wounds were categorized as bacterial infection when treated definitively as such (eg, in the case of sacral ulcers causing osteomyelitis)(NWH, 21; WH, 17). Of note, infectious etiology was associated with intravenous drug use (IVDU) in both NWH and WH patients. Of 184 NWH who reported IVDU, 127 had an infectious diagnosis (P<.001). Similarly, 43 of 56 total WH patients who reported IVDU had an infectious diagnosis (P<.001). Infestation (within the infectious category) included scabies (NWH, 20; WH, 3) and insect or arthropod bites (NWH, 12; WH, 5). Two NWH patients also presented with swelling of the lower extremities and were subsequently diagnosed with maggot infestations. Fungal and viral etiologies were not significantly increased in either group; however, NWH did have a higher incidence of tinea pedis (NWH, 14; WH, 4; P=.03).

More neoplasms (NWH, 6; WH, 16; P=.03), noninfectious inflammatory eruptions (NWH, 48; WH, 85; P<.001), and cutaneous drug eruptions (NWH, 5; WH, 27; P<.001) were reported in WH patients. There was no significant difference in benign vs malignant neoplastic processes between groups. More noninfectious inflammatory eruptions in WH were specifically driven by a markedly increased incidence of follicular (NWH, 9; WH, 29; P<.001) and urticarial/erythematous (NWH, 3; WH, 13; P=.02) lesions. Follicular etiologies included acne (NWH, 1; WH, 6; P=.12), folliculitis (NWH, 5; WH, 2; P=.45), hidradenitis suppurativa (NWH, 2; WH, 11; P=.02), and pilonidal and sebaceous cysts (NWH, 1; WH, 10; P=.01). Allergic urticaria dominated the urticarial/erythematous category (NWH, 3; WH, 11; P=.06), though there were 2 WH presentations of diffuse erythema and skin peeling.

Another substantial proportion of cutaneous etiologies were due to trauma or chronic wounds. Significantly more traumatic injuries presented in NWH patients vs WH patients (36 vs 31; P=.04). Trauma included human or dog bites (NWH, 5; WH, 4), sunburns (NWH, 3; WH, 0), other burns (NWH, 11; WH, 13), abrasions and lacerations (NWH, 16; WH, 3; P=.004), and foreign bodies (NWH, 1; WH, 1). Wounds consisted of chronic wounds such as those due to diabetes mellitus (foot ulcers) or immobility (sacral ulcers); numbers were similar between groups.

Looking at location, NWH patients had more pathology on the feet (NWH, 62; WH, 39; P=.02), whereas WH patients had more disseminated multiregional concerns (NWH, 55; WH, 75; P=.05). No one body location was notably more likely to warrant a chief concern.

For clinical outcomes, more WH patients received a consultation of any kind (NWH, 171; WH, 217; P<.001), consultation to dermatology (NWH, 49; WH, 87; P<.001), and consultation to surgery (NWH, 64; WH, 110; P<.001)(Table 3 and Figure). More outpatient referrals to dermatology were made for WH patients (NWH, 61; WH, 82; P=.05). Notably, NWH patients presented for 80% fewer hospital follow-up appointments (NWH, 11; WH, 55; P<.001). It is essential to note that these findings were not affected by self-reported race or ethnicity. Results remained significant when broken into cohorts consisting of patients with and without skin of color.

Comment

Cutaneous Concerns in NWH Patients—Although cutaneous disease has been reported to disproportionately affect NWH patients,¹⁰ in our cohort, NWH patients had fewer cutaneous chief concerns than WH patients. However, without comparing with all patients entering the ED at UMC, we cannot make a statement on this claim. We do present a few reasons why NWH patients do not have more cutaneous concerns. First, they may wait to present with cutaneous disease until it becomes more severe (eg, until chronic wounds have progressed to infections). Second, as discussed in depth by Hollestein and Nijsten,³ dermatologic disease may be a major contributor to the overall count of disability-adjusted life years but may play a minor role in individual disability. Therefore, skin disease often is considered less important on an individual basis, despite substantial psychosocial burden, leading to further stigmatization of this vulnerable population and discouraged care-seeking behavior, particularly for noninfectious inflammatory eruptions, which were notably more present in WH individuals. Third, fewer dermatologic lesions were reported on NWH patients, which may explain why all 3 WH pigmented lesions were diagnosed after presentation with a noncutaneous concern (eg, headache, anemia, nausea).

Infectious Cutaneous Diagnoses—The increased presentation of infectious etiologies, especially bacterial, is linked to the increased numbers of IVDUs reported in NWH individuals as well as increased exposure and decreased access to basic hygienic supplies. Intravenous drug use acted as an effect modifier of infectious etiology diagnoses, playing a major role in both NWH and WH cohorts. Although Black and Hispanic individuals as well as individuals with low socioeconomic status have increased proportions of skin cancer, there are inadequate data on the prevalence in NWH individuals.⁴ We found no increase in malignant dermatologic processes in NWH individuals; however, this may be secondary to inadequate screening with a total body skin examination.

Clinical Workup of NWH Patients—Because most NWH individuals present to the ED to receive care, their care compared with WH patients should be considered. In this cohort, WH patients received a less extensive clinical workup. They received almost half as many dermatologic consultations and fewer outpatient referrals to dermatology. Major communication barriers may affect NWH presentation to follow-up, which was drastically lower than WH individuals, as scheduling typically occurs well after discharge from the ED or inpatient unit. We suggest a few alterations to improve dermatologic care for NWH individuals:

• Consider inpatient consultation for serious dermatologic conditions—even if chronic—to improve disease control, considering that many barriers inhibit follow-up in clinic.

• Involve outreach teams, such as the Assertive Community Treatment teams, that assist individuals by delivering medicine for psychiatric disorders, conducting total-body skin examinations, assisting with wound care, providing basic skin barrier creams or medicaments, and carrying information regarding outpatient follow-up.

• Educate ED providers on the most common skin concerns, especially those that fall within the noninfectious inflammatory category, such as hidradenitis suppurativa, which could easily be misdiagnosed as an abscess.

Future Directions—Owing to limitations of a retrospective cohort study, we present several opportunities for further research on this vulnerable population. The severity of disease, especially infectious etiologies, should be graded to determine if NWH patients truly present later in the disease course. The duration and quality of housing for NWH patients could be categorized based on living conditions (eg, on the street vs in a shelter). Although the findings of our NWH cohort presenting to the ED at UMC provide helpful insight into dermatologic disease, these findings may be disparate from those conducted at other locations in the United States. University Medical Center provides care to mostly subsidized insurance plans in a racially diverse community. Improved outcomes for the NWH individuals living in New Orleans start with obtaining a greater understanding of their diseases and where disparities exist that can be bridged with better care.

Acknowledgment—The dataset generated during this study and used for analysis is not publicly available to protect public health information but is available from the corresponding author on reasonable request.

More than half a million individuals are without housing (NWH) on any given night in the United States, as estimated by the US Department of Housing and Urban Development. ¹ Lack of hygiene, increased risk of infection and infestation due to living conditions, and barriers to health care put these individuals at increased risk for disease. ² Skin disease, including fungal infection and acne, are within the top 10 most prevalent diseases worldwide and can cause major psychologic impairment, yet dermatologic concerns and clinical outcomes in NWH patients have not been well characterized. ^2-5 Further, because this vulnerable demographic tends to be underinsured, they frequently present to the emergency department (ED) for management of disease. ^1,6 Survey of common concerns in NWH patients is of utility to consulting dermatologists and nondermatologist providers in the ED, who can familiarize themselves with management of diseases they are more likely to encounter. Few studies examine dermatologic conditions in the ED, and a thorough literature review indicates none have included homelessness as a variable. ^6,7 Additionally, comparison with a matched control group of patients with housing (WH) is limited. ^5,8 We present one of the largest comparisons of cutaneous disease in NWH vs WH patients in a single hospital system to elucidate the types of cutaneous disease that motivate patients to seek care, the location of skin disease, and differences in clinical care.

Methods

A retrospective medical record review of patients seen for an inclusive list of dermatologic diagnoses in the ED or while admitted at University Medical Center New Orleans, Louisiana (UMC), between January 1, 2018, and April 21, 2020, was conducted. This study was qualified as exempt from the institutional review board by Louisiana State University because it proposed zero risk to the patients and remained completely anonymous. Eight hundred forty-two total medical records were reviewed (NWH, 421; WH, 421)(Table 1). Patients with housing were matched based on self-identified race and ethnicity, sex, and age. Disease categories were constructed based on fundamental pathophysiology adapted from Dermatology⁹: infectious, noninfectious inflammatory, neoplasm, trauma and wounds, drug-related eruptions, vascular, pruritic, pigmented, bullous, neuropsychiatric, and other. Other included unspecified eruptions as well as miscellaneous lesions such as calluses. The current chief concern, anatomic location, and configuration were recorded, as well as biopsied lesions and outpatient referrals or inpatient consultations to dermatology or other specialties, including wound care, infectious disease, podiatry, and surgery. χ² analysis was used to analyze significance of cutaneous categories, body location, and referrals. Groups smaller than 5 defaulted to the Fisher exact test.

Results

The total diagnoses (including both chief concerns and secondary diagnoses) are shown in Table 2. Chief concerns were more frequently cutaneous or dermatologic for WH (NWH, 209; WH, 307; P<.001). In both groups, cutaneous infectious etiologies were more likely to be a patient’s presenting chief concern (58% NWH, P=.002; 42% WH, P<.001). Noninfectious inflammatory etiologies and pigmented lesions were more likely to be secondary diagnoses with an unrelated noncutaneous concern; noninfectious inflammatory etiologies were only 16% of the total cutaneous chief concerns (11% NWH, P=.04; 20% WH, P=.03), and no pigmented lesions were chief concerns.

Infection was the most common chief concern, though NWH patients presented with significantly more infectious concerns (NWH, 212; WH, 150; P<.001), particularly infestations (NWH, 33; WH, 8; P<.001) and bacterial etiologies (NWH, 127; WH, 100; P=.04). The majority of bacterial etiologies were either an abscess or cellulitis (NWH, 106; WH, 83), though infected chronic wounds were categorized as bacterial infection when treated definitively as such (eg, in the case of sacral ulcers causing osteomyelitis)(NWH, 21; WH, 17). Of note, infectious etiology was associated with intravenous drug use (IVDU) in both NWH and WH patients. Of 184 NWH who reported IVDU, 127 had an infectious diagnosis (P<.001). Similarly, 43 of 56 total WH patients who reported IVDU had an infectious diagnosis (P<.001). Infestation (within the infectious category) included scabies (NWH, 20; WH, 3) and insect or arthropod bites (NWH, 12; WH, 5). Two NWH patients also presented with swelling of the lower extremities and were subsequently diagnosed with maggot infestations. Fungal and viral etiologies were not significantly increased in either group; however, NWH did have a higher incidence of tinea pedis (NWH, 14; WH, 4; P=.03).

More neoplasms (NWH, 6; WH, 16; P=.03), noninfectious inflammatory eruptions (NWH, 48; WH, 85; P<.001), and cutaneous drug eruptions (NWH, 5; WH, 27; P<.001) were reported in WH patients. There was no significant difference in benign vs malignant neoplastic processes between groups. More noninfectious inflammatory eruptions in WH were specifically driven by a markedly increased incidence of follicular (NWH, 9; WH, 29; P<.001) and urticarial/erythematous (NWH, 3; WH, 13; P=.02) lesions. Follicular etiologies included acne (NWH, 1; WH, 6; P=.12), folliculitis (NWH, 5; WH, 2; P=.45), hidradenitis suppurativa (NWH, 2; WH, 11; P=.02), and pilonidal and sebaceous cysts (NWH, 1; WH, 10; P=.01). Allergic urticaria dominated the urticarial/erythematous category (NWH, 3; WH, 11; P=.06), though there were 2 WH presentations of diffuse erythema and skin peeling.

Another substantial proportion of cutaneous etiologies were due to trauma or chronic wounds. Significantly more traumatic injuries presented in NWH patients vs WH patients (36 vs 31; P=.04). Trauma included human or dog bites (NWH, 5; WH, 4), sunburns (NWH, 3; WH, 0), other burns (NWH, 11; WH, 13), abrasions and lacerations (NWH, 16; WH, 3; P=.004), and foreign bodies (NWH, 1; WH, 1). Wounds consisted of chronic wounds such as those due to diabetes mellitus (foot ulcers) or immobility (sacral ulcers); numbers were similar between groups.

Looking at location, NWH patients had more pathology on the feet (NWH, 62; WH, 39; P=.02), whereas WH patients had more disseminated multiregional concerns (NWH, 55; WH, 75; P=.05). No one body location was notably more likely to warrant a chief concern.

For clinical outcomes, more WH patients received a consultation of any kind (NWH, 171; WH, 217; P<.001), consultation to dermatology (NWH, 49; WH, 87; P<.001), and consultation to surgery (NWH, 64; WH, 110; P<.001)(Table 3 and Figure). More outpatient referrals to dermatology were made for WH patients (NWH, 61; WH, 82; P=.05). Notably, NWH patients presented for 80% fewer hospital follow-up appointments (NWH, 11; WH, 55; P<.001). It is essential to note that these findings were not affected by self-reported race or ethnicity. Results remained significant when broken into cohorts consisting of patients with and without skin of color.

Comment

Cutaneous Concerns in NWH Patients—Although cutaneous disease has been reported to disproportionately affect NWH patients,¹⁰ in our cohort, NWH patients had fewer cutaneous chief concerns than WH patients. However, without comparing with all patients entering the ED at UMC, we cannot make a statement on this claim. We do present a few reasons why NWH patients do not have more cutaneous concerns. First, they may wait to present with cutaneous disease until it becomes more severe (eg, until chronic wounds have progressed to infections). Second, as discussed in depth by Hollestein and Nijsten,³ dermatologic disease may be a major contributor to the overall count of disability-adjusted life years but may play a minor role in individual disability. Therefore, skin disease often is considered less important on an individual basis, despite substantial psychosocial burden, leading to further stigmatization of this vulnerable population and discouraged care-seeking behavior, particularly for noninfectious inflammatory eruptions, which were notably more present in WH individuals. Third, fewer dermatologic lesions were reported on NWH patients, which may explain why all 3 WH pigmented lesions were diagnosed after presentation with a noncutaneous concern (eg, headache, anemia, nausea).

Infectious Cutaneous Diagnoses—The increased presentation of infectious etiologies, especially bacterial, is linked to the increased numbers of IVDUs reported in NWH individuals as well as increased exposure and decreased access to basic hygienic supplies. Intravenous drug use acted as an effect modifier of infectious etiology diagnoses, playing a major role in both NWH and WH cohorts. Although Black and Hispanic individuals as well as individuals with low socioeconomic status have increased proportions of skin cancer, there are inadequate data on the prevalence in NWH individuals.⁴ We found no increase in malignant dermatologic processes in NWH individuals; however, this may be secondary to inadequate screening with a total body skin examination.

Clinical Workup of NWH Patients—Because most NWH individuals present to the ED to receive care, their care compared with WH patients should be considered. In this cohort, WH patients received a less extensive clinical workup. They received almost half as many dermatologic consultations and fewer outpatient referrals to dermatology. Major communication barriers may affect NWH presentation to follow-up, which was drastically lower than WH individuals, as scheduling typically occurs well after discharge from the ED or inpatient unit. We suggest a few alterations to improve dermatologic care for NWH individuals:

• Consider inpatient consultation for serious dermatologic conditions—even if chronic—to improve disease control, considering that many barriers inhibit follow-up in clinic.

• Involve outreach teams, such as the Assertive Community Treatment teams, that assist individuals by delivering medicine for psychiatric disorders, conducting total-body skin examinations, assisting with wound care, providing basic skin barrier creams or medicaments, and carrying information regarding outpatient follow-up.

• Educate ED providers on the most common skin concerns, especially those that fall within the noninfectious inflammatory category, such as hidradenitis suppurativa, which could easily be misdiagnosed as an abscess.

Future Directions—Owing to limitations of a retrospective cohort study, we present several opportunities for further research on this vulnerable population. The severity of disease, especially infectious etiologies, should be graded to determine if NWH patients truly present later in the disease course. The duration and quality of housing for NWH patients could be categorized based on living conditions (eg, on the street vs in a shelter). Although the findings of our NWH cohort presenting to the ED at UMC provide helpful insight into dermatologic disease, these findings may be disparate from those conducted at other locations in the United States. University Medical Center provides care to mostly subsidized insurance plans in a racially diverse community. Improved outcomes for the NWH individuals living in New Orleans start with obtaining a greater understanding of their diseases and where disparities exist that can be bridged with better care.

Acknowledgment—The dataset generated during this study and used for analysis is not publicly available to protect public health information but is available from the corresponding author on reasonable request.

More than half a million individuals are without housing (NWH) on any given night in the United States, as estimated by the US Department of Housing and Urban Development. ¹ Lack of hygiene, increased risk of infection and infestation due to living conditions, and barriers to health care put these individuals at increased risk for disease. ² Skin disease, including fungal infection and acne, are within the top 10 most prevalent diseases worldwide and can cause major psychologic impairment, yet dermatologic concerns and clinical outcomes in NWH patients have not been well characterized. ^2-5 Further, because this vulnerable demographic tends to be underinsured, they frequently present to the emergency department (ED) for management of disease. ^1,6 Survey of common concerns in NWH patients is of utility to consulting dermatologists and nondermatologist providers in the ED, who can familiarize themselves with management of diseases they are more likely to encounter. Few studies examine dermatologic conditions in the ED, and a thorough literature review indicates none have included homelessness as a variable. ^6,7 Additionally, comparison with a matched control group of patients with housing (WH) is limited. ^5,8 We present one of the largest comparisons of cutaneous disease in NWH vs WH patients in a single hospital system to elucidate the types of cutaneous disease that motivate patients to seek care, the location of skin disease, and differences in clinical care.

Methods

A retrospective medical record review of patients seen for an inclusive list of dermatologic diagnoses in the ED or while admitted at University Medical Center New Orleans, Louisiana (UMC), between January 1, 2018, and April 21, 2020, was conducted. This study was qualified as exempt from the institutional review board by Louisiana State University because it proposed zero risk to the patients and remained completely anonymous. Eight hundred forty-two total medical records were reviewed (NWH, 421; WH, 421)(Table 1). Patients with housing were matched based on self-identified race and ethnicity, sex, and age. Disease categories were constructed based on fundamental pathophysiology adapted from Dermatology⁹: infectious, noninfectious inflammatory, neoplasm, trauma and wounds, drug-related eruptions, vascular, pruritic, pigmented, bullous, neuropsychiatric, and other. Other included unspecified eruptions as well as miscellaneous lesions such as calluses. The current chief concern, anatomic location, and configuration were recorded, as well as biopsied lesions and outpatient referrals or inpatient consultations to dermatology or other specialties, including wound care, infectious disease, podiatry, and surgery. χ² analysis was used to analyze significance of cutaneous categories, body location, and referrals. Groups smaller than 5 defaulted to the Fisher exact test.

Results

The total diagnoses (including both chief concerns and secondary diagnoses) are shown in Table 2. Chief concerns were more frequently cutaneous or dermatologic for WH (NWH, 209; WH, 307; P<.001). In both groups, cutaneous infectious etiologies were more likely to be a patient’s presenting chief concern (58% NWH, P=.002; 42% WH, P<.001). Noninfectious inflammatory etiologies and pigmented lesions were more likely to be secondary diagnoses with an unrelated noncutaneous concern; noninfectious inflammatory etiologies were only 16% of the total cutaneous chief concerns (11% NWH, P=.04; 20% WH, P=.03), and no pigmented lesions were chief concerns.

Infection was the most common chief concern, though NWH patients presented with significantly more infectious concerns (NWH, 212; WH, 150; P<.001), particularly infestations (NWH, 33; WH, 8; P<.001) and bacterial etiologies (NWH, 127; WH, 100; P=.04). The majority of bacterial etiologies were either an abscess or cellulitis (NWH, 106; WH, 83), though infected chronic wounds were categorized as bacterial infection when treated definitively as such (eg, in the case of sacral ulcers causing osteomyelitis)(NWH, 21; WH, 17). Of note, infectious etiology was associated with intravenous drug use (IVDU) in both NWH and WH patients. Of 184 NWH who reported IVDU, 127 had an infectious diagnosis (P<.001). Similarly, 43 of 56 total WH patients who reported IVDU had an infectious diagnosis (P<.001). Infestation (within the infectious category) included scabies (NWH, 20; WH, 3) and insect or arthropod bites (NWH, 12; WH, 5). Two NWH patients also presented with swelling of the lower extremities and were subsequently diagnosed with maggot infestations. Fungal and viral etiologies were not significantly increased in either group; however, NWH did have a higher incidence of tinea pedis (NWH, 14; WH, 4; P=.03).

More neoplasms (NWH, 6; WH, 16; P=.03), noninfectious inflammatory eruptions (NWH, 48; WH, 85; P<.001), and cutaneous drug eruptions (NWH, 5; WH, 27; P<.001) were reported in WH patients. There was no significant difference in benign vs malignant neoplastic processes between groups. More noninfectious inflammatory eruptions in WH were specifically driven by a markedly increased incidence of follicular (NWH, 9; WH, 29; P<.001) and urticarial/erythematous (NWH, 3; WH, 13; P=.02) lesions. Follicular etiologies included acne (NWH, 1; WH, 6; P=.12), folliculitis (NWH, 5; WH, 2; P=.45), hidradenitis suppurativa (NWH, 2; WH, 11; P=.02), and pilonidal and sebaceous cysts (NWH, 1; WH, 10; P=.01). Allergic urticaria dominated the urticarial/erythematous category (NWH, 3; WH, 11; P=.06), though there were 2 WH presentations of diffuse erythema and skin peeling.

Another substantial proportion of cutaneous etiologies were due to trauma or chronic wounds. Significantly more traumatic injuries presented in NWH patients vs WH patients (36 vs 31; P=.04). Trauma included human or dog bites (NWH, 5; WH, 4), sunburns (NWH, 3; WH, 0), other burns (NWH, 11; WH, 13), abrasions and lacerations (NWH, 16; WH, 3; P=.004), and foreign bodies (NWH, 1; WH, 1). Wounds consisted of chronic wounds such as those due to diabetes mellitus (foot ulcers) or immobility (sacral ulcers); numbers were similar between groups.

Looking at location, NWH patients had more pathology on the feet (NWH, 62; WH, 39; P=.02), whereas WH patients had more disseminated multiregional concerns (NWH, 55; WH, 75; P=.05). No one body location was notably more likely to warrant a chief concern.

For clinical outcomes, more WH patients received a consultation of any kind (NWH, 171; WH, 217; P<.001), consultation to dermatology (NWH, 49; WH, 87; P<.001), and consultation to surgery (NWH, 64; WH, 110; P<.001)(Table 3 and Figure). More outpatient referrals to dermatology were made for WH patients (NWH, 61; WH, 82; P=.05). Notably, NWH patients presented for 80% fewer hospital follow-up appointments (NWH, 11; WH, 55; P<.001). It is essential to note that these findings were not affected by self-reported race or ethnicity. Results remained significant when broken into cohorts consisting of patients with and without skin of color.

Comment

Cutaneous Concerns in NWH Patients—Although cutaneous disease has been reported to disproportionately affect NWH patients,¹⁰ in our cohort, NWH patients had fewer cutaneous chief concerns than WH patients. However, without comparing with all patients entering the ED at UMC, we cannot make a statement on this claim. We do present a few reasons why NWH patients do not have more cutaneous concerns. First, they may wait to present with cutaneous disease until it becomes more severe (eg, until chronic wounds have progressed to infections). Second, as discussed in depth by Hollestein and Nijsten,³ dermatologic disease may be a major contributor to the overall count of disability-adjusted life years but may play a minor role in individual disability. Therefore, skin disease often is considered less important on an individual basis, despite substantial psychosocial burden, leading to further stigmatization of this vulnerable population and discouraged care-seeking behavior, particularly for noninfectious inflammatory eruptions, which were notably more present in WH individuals. Third, fewer dermatologic lesions were reported on NWH patients, which may explain why all 3 WH pigmented lesions were diagnosed after presentation with a noncutaneous concern (eg, headache, anemia, nausea).

Infectious Cutaneous Diagnoses—The increased presentation of infectious etiologies, especially bacterial, is linked to the increased numbers of IVDUs reported in NWH individuals as well as increased exposure and decreased access to basic hygienic supplies. Intravenous drug use acted as an effect modifier of infectious etiology diagnoses, playing a major role in both NWH and WH cohorts. Although Black and Hispanic individuals as well as individuals with low socioeconomic status have increased proportions of skin cancer, there are inadequate data on the prevalence in NWH individuals.⁴ We found no increase in malignant dermatologic processes in NWH individuals; however, this may be secondary to inadequate screening with a total body skin examination.

Clinical Workup of NWH Patients—Because most NWH individuals present to the ED to receive care, their care compared with WH patients should be considered. In this cohort, WH patients received a less extensive clinical workup. They received almost half as many dermatologic consultations and fewer outpatient referrals to dermatology. Major communication barriers may affect NWH presentation to follow-up, which was drastically lower than WH individuals, as scheduling typically occurs well after discharge from the ED or inpatient unit. We suggest a few alterations to improve dermatologic care for NWH individuals:

• Consider inpatient consultation for serious dermatologic conditions—even if chronic—to improve disease control, considering that many barriers inhibit follow-up in clinic.

• Involve outreach teams, such as the Assertive Community Treatment teams, that assist individuals by delivering medicine for psychiatric disorders, conducting total-body skin examinations, assisting with wound care, providing basic skin barrier creams or medicaments, and carrying information regarding outpatient follow-up.

• Educate ED providers on the most common skin concerns, especially those that fall within the noninfectious inflammatory category, such as hidradenitis suppurativa, which could easily be misdiagnosed as an abscess.

Future Directions—Owing to limitations of a retrospective cohort study, we present several opportunities for further research on this vulnerable population. The severity of disease, especially infectious etiologies, should be graded to determine if NWH patients truly present later in the disease course. The duration and quality of housing for NWH patients could be categorized based on living conditions (eg, on the street vs in a shelter). Although the findings of our NWH cohort presenting to the ED at UMC provide helpful insight into dermatologic disease, these findings may be disparate from those conducted at other locations in the United States. University Medical Center provides care to mostly subsidized insurance plans in a racially diverse community. Improved outcomes for the NWH individuals living in New Orleans start with obtaining a greater understanding of their diseases and where disparities exist that can be bridged with better care.

Acknowledgment—The dataset generated during this study and used for analysis is not publicly available to protect public health information but is available from the corresponding author on reasonable request.

Dedicator of cytokinesis 8 (DOCK8 ) deficiency is the major cause of autosomal-recessive hyper-IgEsyndrome. ¹ Characteristic clinical features including eosinophilia, eczema, and recurrent Staphylococcus aureus cutaneous and respiratory tract infections are common in DOCK8 deficiency, similar to the autosomal-dominant form of hyper-IgE syndrome that is due to defi c iency of signal transducer and activation of transcription 3 (STAT-3 ). ¹ In addition, patients with DOCK8 deficiency are particularly susceptible to asthma; food allergies; lymphomas; and severe cutaneous viral infections, including herpes simplex virus (HSV), molluscum contagiosum, varicella-zoster virus, and human papillomavirus. Since the discovery of the DOCK8 gene in 2009, various studies have sought to elucidate the mechanistic contribution of DOCK8 to the dermatologic immune environment. ² Although cutaneous viral infections such as those caused by HSV typically are short lived and self-limiting in immunocompetent hosts, they have proven to be severe and recalcitrant in the setting of DOCK8 deficiency. ¹ Herein, we report the case of a 32-month-old girl with homozygous DOCK8 deficiency who developed acyclovir-resistant cutaneous HSV. 

Case Report

A 32-month-old girl presented with an approximately 2-cm linear erosion along the left posterior auricular sulcus at month 9 of a hospital stay for recurrent infections. Her medical history was notable for multiple upper respiratory tract infections, diffuse eczema, and food allergies. She had presented to an outside hospital at 14 months of age with herpetic gingivostomatitis and eczema herpeticum that was successfully treated with acyclovir. She was readmitted at 20 months of age due to Pneumocystis jiroveci pneumonia, pancytopenia, and disseminated histoplasmosis. Prophylactic oral acyclovir (20 mg/kg twice daily) was started, given her history of HSV infection. Because of recurrent infections, she underwent an immunodeficiency workup. Whole exome sequencing analysis revealed a homozygous deletion c.(528+1_529−1)_(1516+1_1517−1)del in DOCK8 gene–affecting exons 5 to 13. The patient was transferred to our hospital for continued care and as a potential candidate for bone marrow transplant following resolution of the disseminated histoplasmosis infection.

During her hospitalization at the current presentation, she was noted to have a 2-cm linear erosion along the left posterior auricular sulcus. Initial wound care with bacitracin ointment was applied to the area while specimens were obtained and empiric oral acyclovir therapy was initiated (20 mg/kg 4 times daily [QID]), given a clinical impression consistent with cutaneous HSV infection despite acyclovir prophylaxis. Direct immunofluorescence and viral cultures were positive for HSV-1, while bacterial cultures grew methicillin-susceptible S aureus. Cephalexin and mupirocin ointment were started, and acyclovir was continued. After 2 weeks of therapy, there was no visible change in the wound; cultures were repeated, again showing the wound contained HSV. Bacterial cultures this time grew Pseudomonas putida, and the antibiotic regimen was transitioned to cefepime.

After no response to the continued course of therapeutic acyclovir, HSV cultures were sent to the Centers for Disease Control and Prevention for resistance testing, and biopsy of the lesion was performed by the otolaryngology service to rule out malignancy and potential alternative diagnoses. Histopathology showed only reactive inflammation without visible microorganisms on tissue HSV-1/HSV-2 immunostain; however, tissue viral culture was positive for HSV-1. The patient was transitioned back to acyclovir (intravenous [IV] 20 mg/kg QID) with the addition of empiric foscarnet (IV 40 mg/kg 3 times daily) given the worsening appearance of the lesion.  The HSV acyclovir resistance test results from the Centers for Disease Control and Prevention returned soon after and were positive for resistance (median infectious dose, 3.29 µg/L [reference interval, sensitive <2.00 µg/L; resistant >1.90 µg/L]). The patient completed a 21-day course of combination foscarnet and acyclovir therapy, during which time the lesion showed notable improvement and healing. The patient was continued on prophylactic acyclovir (IV 20 mg/kg QID). Unfortunately, the patient eventually died due to complications related to pneumonia.

Comment

Infection in Patients With DOCK8 Deficiency—The gene DOCK8 has emerged as playing a central role in both innate and adaptive immunity, as it is expressed primarily in immune cells and serves as a mediator of numerous processes, including immune synapse formation, cell signaling and trafficking, antibody and cytokine production, and lymphocyte memory.³ Cells that are critical for combating cutaneous viral infections, including skin-resident memory T cells and natural killer cells, are defective, which leads to a severely immunocompromised state in DOCK8-deficient patients with a particular susceptibility to infectious and inflammatory dermatologic disease.⁴ 

Herpes simplex virus infection commonly is seen in DOCK8 deficiency, with retrospective analysis of a DOCK8-deficient cohort revealing HSV infection in approximately 38% of patients.⁵ Prophylactic acyclovir is essential for DOCK8-deficient individuals with a history of HSV infection given the tendency of the virus to reactivate.⁶ However, despite prophylaxis, our patient developed an HSV-positive posterior auricular erosion that continued to progress even after increase of the acyclovir dose. Acyclovir resistance testing of the HSV isolated from the wound was positive, confirming the clinical suspicion of the presence of acyclovir-resistant HSV infection.

Acyclovir-Resistant HSV—Acyclovir-resistant HSV in immunosuppressed individuals was first noted in 1982, and most cases since then have occurred in the setting of AIDS and in organ transplant recipients.⁶ Few reports of acyclovir-resistant HSV in DOCK8 deficiency exist, and to our knowledge, our patient is the youngest DOCK8-deficient individual to be documented with acyclovir-resistant HSV infection.^1,7-15 We identified relevant cases from the PubMed and EMBASE databases using the search terms DOCK8 deficiency and acyclovir and DOCK8 deficiency and herpes. The eTable lists other reported cases of acyclovir-resistant HSV in DOCK8-deficient patients. The majority of cases involved school-aged females. Lesion types varied and included herpes labialis, eczema herpeticum, and blepharoconjunctivitis. Escalation of therapy and resolution of the lesion was seen in some cases with administration of subcutaneous pegylated interferon alfa-2b.

Treatment Alternatives—Acyclovir competitively inhibits viral DNA polymerase by incorporating into elongating viral DNA strands and halting chain synthesis. Acyclovir requires triphosphorylation for activation, and viral thymidine kinase is responsible for the first phosphorylation event. Ninety-five percent of cases of acyclovir resistance are secondary to mutations in viral thymidine kinase. Foscarnet also inhibits viral DNA polymerase but does so directly without the need to be phosphorylated first.⁶ For this reason, foscarnet often is the drug of choice in the treatment of acyclovir-resistant HSV, as evidenced in our patient. However, foscarnet-resistant HSV strains may develop from mutations in the DNA polymerase gene.

Cidofovir is a nucleotide analogue that requires phosphorylation by host, as opposed to viral, kinases for antiviral activity. Intravenous and topical formulations of cidofovir have proven effective in the treatment of acyclovir- and foscarnet-resistant HSV lesions.⁶ Cidofovir also can be applied intralesionally, a method that provides targeted therapy and minimizes cidofovir-associated nephrotoxicity.¹² Reports of systemic interferon alfa therapy for acyclovir-resistant HSV also exist. A study found IFN-⍺ production by peripheral blood mononuclear cells in DOCK8-deficient individuals to be significantly reduced relative to controls (P<.05).⁷ There has been complete resolution of acyclovir-resistant HSV lesions with subcutaneous pegylated interferon alfa-2b injections in several DOCK8-deficient patients.^7-9

The need for escalating therapy in DOCK8-deficient individuals with acyclovir-resistant HSV infection underscores the essential role of DOCK8 in dermatologic immunity. Our case demonstrates that a high degree of suspicion for cutaneous HSV infection should be adopted in DOCK8-deficient patients of any age, regardless of acyclovir prophylaxis. Viral culture in addition to bacterial cultures should be performed early in patients with cutaneous erosions, and the threshold for HSV resistance testing should be low to minimize morbidity associated with these infections. Early resistance testing in our case could have prevented prolongation of infection and likely eliminated the need for a biopsy.

Conclusion

DOCK8 deficiency presents a unique challenge to dermatologists and other health care providers given the susceptibility of affected individuals to developing a reservoir of severe and potentially resistant viral cutaneous infections. Prophylactic acyclovir may not be sufficient for HSV suppression, even in the youngest of patients, and suspicion for resistance should be high to avoid delays in adequate treatment.

Dedicator of cytokinesis 8 (DOCK8 ) deficiency is the major cause of autosomal-recessive hyper-IgEsyndrome. ¹ Characteristic clinical features including eosinophilia, eczema, and recurrent Staphylococcus aureus cutaneous and respiratory tract infections are common in DOCK8 deficiency, similar to the autosomal-dominant form of hyper-IgE syndrome that is due to defi c iency of signal transducer and activation of transcription 3 (STAT-3 ). ¹ In addition, patients with DOCK8 deficiency are particularly susceptible to asthma; food allergies; lymphomas; and severe cutaneous viral infections, including herpes simplex virus (HSV), molluscum contagiosum, varicella-zoster virus, and human papillomavirus. Since the discovery of the DOCK8 gene in 2009, various studies have sought to elucidate the mechanistic contribution of DOCK8 to the dermatologic immune environment. ² Although cutaneous viral infections such as those caused by HSV typically are short lived and self-limiting in immunocompetent hosts, they have proven to be severe and recalcitrant in the setting of DOCK8 deficiency. ¹ Herein, we report the case of a 32-month-old girl with homozygous DOCK8 deficiency who developed acyclovir-resistant cutaneous HSV. 

Case Report

A 32-month-old girl presented with an approximately 2-cm linear erosion along the left posterior auricular sulcus at month 9 of a hospital stay for recurrent infections. Her medical history was notable for multiple upper respiratory tract infections, diffuse eczema, and food allergies. She had presented to an outside hospital at 14 months of age with herpetic gingivostomatitis and eczema herpeticum that was successfully treated with acyclovir. She was readmitted at 20 months of age due to Pneumocystis jiroveci pneumonia, pancytopenia, and disseminated histoplasmosis. Prophylactic oral acyclovir (20 mg/kg twice daily) was started, given her history of HSV infection. Because of recurrent infections, she underwent an immunodeficiency workup. Whole exome sequencing analysis revealed a homozygous deletion c.(528+1_529−1)_(1516+1_1517−1)del in DOCK8 gene–affecting exons 5 to 13. The patient was transferred to our hospital for continued care and as a potential candidate for bone marrow transplant following resolution of the disseminated histoplasmosis infection.

During her hospitalization at the current presentation, she was noted to have a 2-cm linear erosion along the left posterior auricular sulcus. Initial wound care with bacitracin ointment was applied to the area while specimens were obtained and empiric oral acyclovir therapy was initiated (20 mg/kg 4 times daily [QID]), given a clinical impression consistent with cutaneous HSV infection despite acyclovir prophylaxis. Direct immunofluorescence and viral cultures were positive for HSV-1, while bacterial cultures grew methicillin-susceptible S aureus. Cephalexin and mupirocin ointment were started, and acyclovir was continued. After 2 weeks of therapy, there was no visible change in the wound; cultures were repeated, again showing the wound contained HSV. Bacterial cultures this time grew Pseudomonas putida, and the antibiotic regimen was transitioned to cefepime.

After no response to the continued course of therapeutic acyclovir, HSV cultures were sent to the Centers for Disease Control and Prevention for resistance testing, and biopsy of the lesion was performed by the otolaryngology service to rule out malignancy and potential alternative diagnoses. Histopathology showed only reactive inflammation without visible microorganisms on tissue HSV-1/HSV-2 immunostain; however, tissue viral culture was positive for HSV-1. The patient was transitioned back to acyclovir (intravenous [IV] 20 mg/kg QID) with the addition of empiric foscarnet (IV 40 mg/kg 3 times daily) given the worsening appearance of the lesion.  The HSV acyclovir resistance test results from the Centers for Disease Control and Prevention returned soon after and were positive for resistance (median infectious dose, 3.29 µg/L [reference interval, sensitive <2.00 µg/L; resistant >1.90 µg/L]). The patient completed a 21-day course of combination foscarnet and acyclovir therapy, during which time the lesion showed notable improvement and healing. The patient was continued on prophylactic acyclovir (IV 20 mg/kg QID). Unfortunately, the patient eventually died due to complications related to pneumonia.

Comment

Infection in Patients With DOCK8 Deficiency—The gene DOCK8 has emerged as playing a central role in both innate and adaptive immunity, as it is expressed primarily in immune cells and serves as a mediator of numerous processes, including immune synapse formation, cell signaling and trafficking, antibody and cytokine production, and lymphocyte memory.³ Cells that are critical for combating cutaneous viral infections, including skin-resident memory T cells and natural killer cells, are defective, which leads to a severely immunocompromised state in DOCK8-deficient patients with a particular susceptibility to infectious and inflammatory dermatologic disease.⁴ 

Herpes simplex virus infection commonly is seen in DOCK8 deficiency, with retrospective analysis of a DOCK8-deficient cohort revealing HSV infection in approximately 38% of patients.⁵ Prophylactic acyclovir is essential for DOCK8-deficient individuals with a history of HSV infection given the tendency of the virus to reactivate.⁶ However, despite prophylaxis, our patient developed an HSV-positive posterior auricular erosion that continued to progress even after increase of the acyclovir dose. Acyclovir resistance testing of the HSV isolated from the wound was positive, confirming the clinical suspicion of the presence of acyclovir-resistant HSV infection.

Acyclovir-Resistant HSV—Acyclovir-resistant HSV in immunosuppressed individuals was first noted in 1982, and most cases since then have occurred in the setting of AIDS and in organ transplant recipients.⁶ Few reports of acyclovir-resistant HSV in DOCK8 deficiency exist, and to our knowledge, our patient is the youngest DOCK8-deficient individual to be documented with acyclovir-resistant HSV infection.^1,7-15 We identified relevant cases from the PubMed and EMBASE databases using the search terms DOCK8 deficiency and acyclovir and DOCK8 deficiency and herpes. The eTable lists other reported cases of acyclovir-resistant HSV in DOCK8-deficient patients. The majority of cases involved school-aged females. Lesion types varied and included herpes labialis, eczema herpeticum, and blepharoconjunctivitis. Escalation of therapy and resolution of the lesion was seen in some cases with administration of subcutaneous pegylated interferon alfa-2b.

Treatment Alternatives—Acyclovir competitively inhibits viral DNA polymerase by incorporating into elongating viral DNA strands and halting chain synthesis. Acyclovir requires triphosphorylation for activation, and viral thymidine kinase is responsible for the first phosphorylation event. Ninety-five percent of cases of acyclovir resistance are secondary to mutations in viral thymidine kinase. Foscarnet also inhibits viral DNA polymerase but does so directly without the need to be phosphorylated first.⁶ For this reason, foscarnet often is the drug of choice in the treatment of acyclovir-resistant HSV, as evidenced in our patient. However, foscarnet-resistant HSV strains may develop from mutations in the DNA polymerase gene.

Cidofovir is a nucleotide analogue that requires phosphorylation by host, as opposed to viral, kinases for antiviral activity. Intravenous and topical formulations of cidofovir have proven effective in the treatment of acyclovir- and foscarnet-resistant HSV lesions.⁶ Cidofovir also can be applied intralesionally, a method that provides targeted therapy and minimizes cidofovir-associated nephrotoxicity.¹² Reports of systemic interferon alfa therapy for acyclovir-resistant HSV also exist. A study found IFN-⍺ production by peripheral blood mononuclear cells in DOCK8-deficient individuals to be significantly reduced relative to controls (P<.05).⁷ There has been complete resolution of acyclovir-resistant HSV lesions with subcutaneous pegylated interferon alfa-2b injections in several DOCK8-deficient patients.^7-9

The need for escalating therapy in DOCK8-deficient individuals with acyclovir-resistant HSV infection underscores the essential role of DOCK8 in dermatologic immunity. Our case demonstrates that a high degree of suspicion for cutaneous HSV infection should be adopted in DOCK8-deficient patients of any age, regardless of acyclovir prophylaxis. Viral culture in addition to bacterial cultures should be performed early in patients with cutaneous erosions, and the threshold for HSV resistance testing should be low to minimize morbidity associated with these infections. Early resistance testing in our case could have prevented prolongation of infection and likely eliminated the need for a biopsy.

Conclusion

DOCK8 deficiency presents a unique challenge to dermatologists and other health care providers given the susceptibility of affected individuals to developing a reservoir of severe and potentially resistant viral cutaneous infections. Prophylactic acyclovir may not be sufficient for HSV suppression, even in the youngest of patients, and suspicion for resistance should be high to avoid delays in adequate treatment.

Dedicator of cytokinesis 8 (DOCK8 ) deficiency is the major cause of autosomal-recessive hyper-IgEsyndrome. ¹ Characteristic clinical features including eosinophilia, eczema, and recurrent Staphylococcus aureus cutaneous and respiratory tract infections are common in DOCK8 deficiency, similar to the autosomal-dominant form of hyper-IgE syndrome that is due to defi c iency of signal transducer and activation of transcription 3 (STAT-3 ). ¹ In addition, patients with DOCK8 deficiency are particularly susceptible to asthma; food allergies; lymphomas; and severe cutaneous viral infections, including herpes simplex virus (HSV), molluscum contagiosum, varicella-zoster virus, and human papillomavirus. Since the discovery of the DOCK8 gene in 2009, various studies have sought to elucidate the mechanistic contribution of DOCK8 to the dermatologic immune environment. ² Although cutaneous viral infections such as those caused by HSV typically are short lived and self-limiting in immunocompetent hosts, they have proven to be severe and recalcitrant in the setting of DOCK8 deficiency. ¹ Herein, we report the case of a 32-month-old girl with homozygous DOCK8 deficiency who developed acyclovir-resistant cutaneous HSV. 

Case Report

A 32-month-old girl presented with an approximately 2-cm linear erosion along the left posterior auricular sulcus at month 9 of a hospital stay for recurrent infections. Her medical history was notable for multiple upper respiratory tract infections, diffuse eczema, and food allergies. She had presented to an outside hospital at 14 months of age with herpetic gingivostomatitis and eczema herpeticum that was successfully treated with acyclovir. She was readmitted at 20 months of age due to Pneumocystis jiroveci pneumonia, pancytopenia, and disseminated histoplasmosis. Prophylactic oral acyclovir (20 mg/kg twice daily) was started, given her history of HSV infection. Because of recurrent infections, she underwent an immunodeficiency workup. Whole exome sequencing analysis revealed a homozygous deletion c.(528+1_529−1)_(1516+1_1517−1)del in DOCK8 gene–affecting exons 5 to 13. The patient was transferred to our hospital for continued care and as a potential candidate for bone marrow transplant following resolution of the disseminated histoplasmosis infection.

During her hospitalization at the current presentation, she was noted to have a 2-cm linear erosion along the left posterior auricular sulcus. Initial wound care with bacitracin ointment was applied to the area while specimens were obtained and empiric oral acyclovir therapy was initiated (20 mg/kg 4 times daily [QID]), given a clinical impression consistent with cutaneous HSV infection despite acyclovir prophylaxis. Direct immunofluorescence and viral cultures were positive for HSV-1, while bacterial cultures grew methicillin-susceptible S aureus. Cephalexin and mupirocin ointment were started, and acyclovir was continued. After 2 weeks of therapy, there was no visible change in the wound; cultures were repeated, again showing the wound contained HSV. Bacterial cultures this time grew Pseudomonas putida, and the antibiotic regimen was transitioned to cefepime.

After no response to the continued course of therapeutic acyclovir, HSV cultures were sent to the Centers for Disease Control and Prevention for resistance testing, and biopsy of the lesion was performed by the otolaryngology service to rule out malignancy and potential alternative diagnoses. Histopathology showed only reactive inflammation without visible microorganisms on tissue HSV-1/HSV-2 immunostain; however, tissue viral culture was positive for HSV-1. The patient was transitioned back to acyclovir (intravenous [IV] 20 mg/kg QID) with the addition of empiric foscarnet (IV 40 mg/kg 3 times daily) given the worsening appearance of the lesion.  The HSV acyclovir resistance test results from the Centers for Disease Control and Prevention returned soon after and were positive for resistance (median infectious dose, 3.29 µg/L [reference interval, sensitive <2.00 µg/L; resistant >1.90 µg/L]). The patient completed a 21-day course of combination foscarnet and acyclovir therapy, during which time the lesion showed notable improvement and healing. The patient was continued on prophylactic acyclovir (IV 20 mg/kg QID). Unfortunately, the patient eventually died due to complications related to pneumonia.

Comment

Infection in Patients With DOCK8 Deficiency—The gene DOCK8 has emerged as playing a central role in both innate and adaptive immunity, as it is expressed primarily in immune cells and serves as a mediator of numerous processes, including immune synapse formation, cell signaling and trafficking, antibody and cytokine production, and lymphocyte memory.³ Cells that are critical for combating cutaneous viral infections, including skin-resident memory T cells and natural killer cells, are defective, which leads to a severely immunocompromised state in DOCK8-deficient patients with a particular susceptibility to infectious and inflammatory dermatologic disease.⁴ 

Herpes simplex virus infection commonly is seen in DOCK8 deficiency, with retrospective analysis of a DOCK8-deficient cohort revealing HSV infection in approximately 38% of patients.⁵ Prophylactic acyclovir is essential for DOCK8-deficient individuals with a history of HSV infection given the tendency of the virus to reactivate.⁶ However, despite prophylaxis, our patient developed an HSV-positive posterior auricular erosion that continued to progress even after increase of the acyclovir dose. Acyclovir resistance testing of the HSV isolated from the wound was positive, confirming the clinical suspicion of the presence of acyclovir-resistant HSV infection.

Acyclovir-Resistant HSV—Acyclovir-resistant HSV in immunosuppressed individuals was first noted in 1982, and most cases since then have occurred in the setting of AIDS and in organ transplant recipients.⁶ Few reports of acyclovir-resistant HSV in DOCK8 deficiency exist, and to our knowledge, our patient is the youngest DOCK8-deficient individual to be documented with acyclovir-resistant HSV infection.^1,7-15 We identified relevant cases from the PubMed and EMBASE databases using the search terms DOCK8 deficiency and acyclovir and DOCK8 deficiency and herpes. The eTable lists other reported cases of acyclovir-resistant HSV in DOCK8-deficient patients. The majority of cases involved school-aged females. Lesion types varied and included herpes labialis, eczema herpeticum, and blepharoconjunctivitis. Escalation of therapy and resolution of the lesion was seen in some cases with administration of subcutaneous pegylated interferon alfa-2b.

Treatment Alternatives—Acyclovir competitively inhibits viral DNA polymerase by incorporating into elongating viral DNA strands and halting chain synthesis. Acyclovir requires triphosphorylation for activation, and viral thymidine kinase is responsible for the first phosphorylation event. Ninety-five percent of cases of acyclovir resistance are secondary to mutations in viral thymidine kinase. Foscarnet also inhibits viral DNA polymerase but does so directly without the need to be phosphorylated first.⁶ For this reason, foscarnet often is the drug of choice in the treatment of acyclovir-resistant HSV, as evidenced in our patient. However, foscarnet-resistant HSV strains may develop from mutations in the DNA polymerase gene.

Cidofovir is a nucleotide analogue that requires phosphorylation by host, as opposed to viral, kinases for antiviral activity. Intravenous and topical formulations of cidofovir have proven effective in the treatment of acyclovir- and foscarnet-resistant HSV lesions.⁶ Cidofovir also can be applied intralesionally, a method that provides targeted therapy and minimizes cidofovir-associated nephrotoxicity.¹² Reports of systemic interferon alfa therapy for acyclovir-resistant HSV also exist. A study found IFN-⍺ production by peripheral blood mononuclear cells in DOCK8-deficient individuals to be significantly reduced relative to controls (P<.05).⁷ There has been complete resolution of acyclovir-resistant HSV lesions with subcutaneous pegylated interferon alfa-2b injections in several DOCK8-deficient patients.^7-9

The need for escalating therapy in DOCK8-deficient individuals with acyclovir-resistant HSV infection underscores the essential role of DOCK8 in dermatologic immunity. Our case demonstrates that a high degree of suspicion for cutaneous HSV infection should be adopted in DOCK8-deficient patients of any age, regardless of acyclovir prophylaxis. Viral culture in addition to bacterial cultures should be performed early in patients with cutaneous erosions, and the threshold for HSV resistance testing should be low to minimize morbidity associated with these infections. Early resistance testing in our case could have prevented prolongation of infection and likely eliminated the need for a biopsy.

Conclusion

DOCK8 deficiency presents a unique challenge to dermatologists and other health care providers given the susceptibility of affected individuals to developing a reservoir of severe and potentially resistant viral cutaneous infections. Prophylactic acyclovir may not be sufficient for HSV suppression, even in the youngest of patients, and suspicion for resistance should be high to avoid delays in adequate treatment.

To the Editor:

Pityriasis rubra pilaris (PRP) is a rare inflammatory dermatosis of unknown etiology characterized by erythematosquamous salmon-colored plaques with well-demarcated islands of unaffected skin and hyperkeratotic follicles.¹ In the United States, an incidence of 1 in 3500to 5000 patients presenting to dermatology clinics has been reported.² Pityriasis rubra pilaris has several subtypes and variability in presentation that can make accurate and timely diagnosis challenging.^3-5 Herein, we present a case of PRP with complex diagnostic and therapeutic challenges.

A 22-year-old woman presented with symmetrical, well-demarcated, hyperkeratotic, erythematous plaques with a carnauba wax–like appearance on the palms (Figure 1), soles, elbows, and trunk covering approximately 5% of the body surface area. Two weeks prior to presentation, she experienced an upper respiratory tract infection without any treatment and subsequently developed redness on the palms, which became very hard and scaly. The redness then spread to the elbows, soles, and trunk. She reported itching as well as pain in areas of fissuring. Hand mobility became restricted due to thick scale.

The patient’s medical history was notable for suspected psoriasis 9 years prior, but there were no records or biopsy reports that could be obtained to confirm the diagnosis. She also reported a similar skin condition in her father, which also was diagnosed as psoriasis, but this diagnosis could not be verified.

Although the morphology of the lesions was most consistent with localized PRP, atypical psoriasis, palmoplantar keratoderma (PPK), and erythroderma progressive symmetrica (EPS) also were considered given the personal and family history of suspected psoriasis. A biopsy could not be obtained due to an insurance issue. She was started on clobetasol cream 0.05% and ointment. At 2-week follow-up, her condition remained unchanged. Empiric systemic treatment was discussed, which would potentially work for diagnoses of both PRP and psoriasis. Due to the history of psoriasis and level of discomfort, cyclosporine 300 mg once daily was started to gain rapid control of the disease. Methotrexate also was considered due to its efficacy and economic considerations but was not selected due to patient concerns about the medication.

After 10 weeks of cyclosporine treatment, our patient showed some improvement of the skin with decreased scale and flattening of plaques but not complete resolution. At this point, a biopsy was able to be obtained with prior authorization. A 4-mm punch biopsy of the right flank demonstrated a psoriasiform and papillated epidermis with multifocally capped, compact parakeratosis and minimal lymphocytic infiltrate consistent with PRP. Although EPS also was on the histologic differential, clinical history was more consistent with a diagnosis of PRP. There was some minimal improvement with cyclosporine, but with the diagnosis of PRP confirmed, a systemic retinoid became the treatment of choice. Although acitretin is the preferred treatment for PRP, given that pregnancy would be contraindicated during and for 3 years following acitretin therapy, a trial of isotretinoin 40 mg once daily was started due to its shorter half-life compared to acitretin and was continued for 3 months (Figure 2).^6,7

The diagnosis of PRP often can be challenging given the variety of clinical presentations. This case was an atypical presentation of PRP with several learning points, as our patient’s condition did not fit perfectly into any of the 6 types of PRP. The age of onset was atypical at 22 years old. Pityriasis rubra pilaris typically presents with a bimodal age distribution, appearing either in the first decade or the fifth to sixth decades of life.^3,8 Her clinical presentation was atypical for adult-onset types I and II, which typically present with cephalocaudal progression or ichthyosiform dermatitis, respectively. Her presentation also was atypical for juvenile onset in types III, IV, and V, which tend to present in younger children and with different physical examination findings.^3,8

The morphology of our patient’s lesions also was atypical for PRP, PPK, EPS, and psoriasis. The clinical presentation had features of these entities with erythema, fissuring, xerosis, carnauba wax–like appearance, symmetric scale, and well-demarcated plaques. Although these findings are not mutually exclusive, their combined presentation is atypical. Coupled with the ambiguous family history of similar skin disease in the patient’s father, the discussion of genodermatoses, particularly PPK, further confounded the diagnosis.^4,9 When evaluating for PRP, especially with any family history of skin conditions, genodermatoses should be considered. Furthermore, our patient’s remote and unverifiable history of psoriasis serves as a cautionary reminder that prior diagnoses and medical history always should be reasonably scrutinized. Additionally, a drug-induced PRP eruption also should be considered. Although our patient received no medical treatment for the upper respiratory tract infection prior to the onset of PRP, there have been several reports of drug-induced PRP.^10-12

The therapeutic challenge in this case is one that often is encountered in clinical practice. The health care system often may pose a barrier to diagnosis by inhibiting particular services required for adequate patient care. For our patient, diagnosis was delayed by several weeks due to difficulties obtaining a diagnostic skin biopsy. When faced with challenges from health care infrastructure, creativity with treatment options, such as finding an empiric treatment option (cyclosporine in this case), must be considered.

Systemic retinoids have been found to be efficacious treatment options for PRP, but when dealing with a woman of reproductive age, reproductive preferences must be discussed before identifying an appropriate treatment regimen.^1,13-15 The half-life of acitretin compared to isotretinoin is 2 days vs 22 hours.^6,16 With alcohol consumption, acitretin can be metabolized to etretinate, which has a half-life of 120 days.¹⁷ In our patient, isotretinoin was a more manageable option to allow for greater reproductive freedom upon treatment completion.

To the Editor:

Pityriasis rubra pilaris (PRP) is a rare inflammatory dermatosis of unknown etiology characterized by erythematosquamous salmon-colored plaques with well-demarcated islands of unaffected skin and hyperkeratotic follicles.¹ In the United States, an incidence of 1 in 3500to 5000 patients presenting to dermatology clinics has been reported.² Pityriasis rubra pilaris has several subtypes and variability in presentation that can make accurate and timely diagnosis challenging.^3-5 Herein, we present a case of PRP with complex diagnostic and therapeutic challenges.

A 22-year-old woman presented with symmetrical, well-demarcated, hyperkeratotic, erythematous plaques with a carnauba wax–like appearance on the palms (Figure 1), soles, elbows, and trunk covering approximately 5% of the body surface area. Two weeks prior to presentation, she experienced an upper respiratory tract infection without any treatment and subsequently developed redness on the palms, which became very hard and scaly. The redness then spread to the elbows, soles, and trunk. She reported itching as well as pain in areas of fissuring. Hand mobility became restricted due to thick scale.

The patient’s medical history was notable for suspected psoriasis 9 years prior, but there were no records or biopsy reports that could be obtained to confirm the diagnosis. She also reported a similar skin condition in her father, which also was diagnosed as psoriasis, but this diagnosis could not be verified.

Although the morphology of the lesions was most consistent with localized PRP, atypical psoriasis, palmoplantar keratoderma (PPK), and erythroderma progressive symmetrica (EPS) also were considered given the personal and family history of suspected psoriasis. A biopsy could not be obtained due to an insurance issue. She was started on clobetasol cream 0.05% and ointment. At 2-week follow-up, her condition remained unchanged. Empiric systemic treatment was discussed, which would potentially work for diagnoses of both PRP and psoriasis. Due to the history of psoriasis and level of discomfort, cyclosporine 300 mg once daily was started to gain rapid control of the disease. Methotrexate also was considered due to its efficacy and economic considerations but was not selected due to patient concerns about the medication.

After 10 weeks of cyclosporine treatment, our patient showed some improvement of the skin with decreased scale and flattening of plaques but not complete resolution. At this point, a biopsy was able to be obtained with prior authorization. A 4-mm punch biopsy of the right flank demonstrated a psoriasiform and papillated epidermis with multifocally capped, compact parakeratosis and minimal lymphocytic infiltrate consistent with PRP. Although EPS also was on the histologic differential, clinical history was more consistent with a diagnosis of PRP. There was some minimal improvement with cyclosporine, but with the diagnosis of PRP confirmed, a systemic retinoid became the treatment of choice. Although acitretin is the preferred treatment for PRP, given that pregnancy would be contraindicated during and for 3 years following acitretin therapy, a trial of isotretinoin 40 mg once daily was started due to its shorter half-life compared to acitretin and was continued for 3 months (Figure 2).^6,7

The diagnosis of PRP often can be challenging given the variety of clinical presentations. This case was an atypical presentation of PRP with several learning points, as our patient’s condition did not fit perfectly into any of the 6 types of PRP. The age of onset was atypical at 22 years old. Pityriasis rubra pilaris typically presents with a bimodal age distribution, appearing either in the first decade or the fifth to sixth decades of life.^3,8 Her clinical presentation was atypical for adult-onset types I and II, which typically present with cephalocaudal progression or ichthyosiform dermatitis, respectively. Her presentation also was atypical for juvenile onset in types III, IV, and V, which tend to present in younger children and with different physical examination findings.^3,8

The morphology of our patient’s lesions also was atypical for PRP, PPK, EPS, and psoriasis. The clinical presentation had features of these entities with erythema, fissuring, xerosis, carnauba wax–like appearance, symmetric scale, and well-demarcated plaques. Although these findings are not mutually exclusive, their combined presentation is atypical. Coupled with the ambiguous family history of similar skin disease in the patient’s father, the discussion of genodermatoses, particularly PPK, further confounded the diagnosis.^4,9 When evaluating for PRP, especially with any family history of skin conditions, genodermatoses should be considered. Furthermore, our patient’s remote and unverifiable history of psoriasis serves as a cautionary reminder that prior diagnoses and medical history always should be reasonably scrutinized. Additionally, a drug-induced PRP eruption also should be considered. Although our patient received no medical treatment for the upper respiratory tract infection prior to the onset of PRP, there have been several reports of drug-induced PRP.^10-12

The therapeutic challenge in this case is one that often is encountered in clinical practice. The health care system often may pose a barrier to diagnosis by inhibiting particular services required for adequate patient care. For our patient, diagnosis was delayed by several weeks due to difficulties obtaining a diagnostic skin biopsy. When faced with challenges from health care infrastructure, creativity with treatment options, such as finding an empiric treatment option (cyclosporine in this case), must be considered.

Systemic retinoids have been found to be efficacious treatment options for PRP, but when dealing with a woman of reproductive age, reproductive preferences must be discussed before identifying an appropriate treatment regimen.^1,13-15 The half-life of acitretin compared to isotretinoin is 2 days vs 22 hours.^6,16 With alcohol consumption, acitretin can be metabolized to etretinate, which has a half-life of 120 days.¹⁷ In our patient, isotretinoin was a more manageable option to allow for greater reproductive freedom upon treatment completion.

To the Editor:

Pityriasis rubra pilaris (PRP) is a rare inflammatory dermatosis of unknown etiology characterized by erythematosquamous salmon-colored plaques with well-demarcated islands of unaffected skin and hyperkeratotic follicles.¹ In the United States, an incidence of 1 in 3500to 5000 patients presenting to dermatology clinics has been reported.² Pityriasis rubra pilaris has several subtypes and variability in presentation that can make accurate and timely diagnosis challenging.^3-5 Herein, we present a case of PRP with complex diagnostic and therapeutic challenges.

A 22-year-old woman presented with symmetrical, well-demarcated, hyperkeratotic, erythematous plaques with a carnauba wax–like appearance on the palms (Figure 1), soles, elbows, and trunk covering approximately 5% of the body surface area. Two weeks prior to presentation, she experienced an upper respiratory tract infection without any treatment and subsequently developed redness on the palms, which became very hard and scaly. The redness then spread to the elbows, soles, and trunk. She reported itching as well as pain in areas of fissuring. Hand mobility became restricted due to thick scale.

The patient’s medical history was notable for suspected psoriasis 9 years prior, but there were no records or biopsy reports that could be obtained to confirm the diagnosis. She also reported a similar skin condition in her father, which also was diagnosed as psoriasis, but this diagnosis could not be verified.

Although the morphology of the lesions was most consistent with localized PRP, atypical psoriasis, palmoplantar keratoderma (PPK), and erythroderma progressive symmetrica (EPS) also were considered given the personal and family history of suspected psoriasis. A biopsy could not be obtained due to an insurance issue. She was started on clobetasol cream 0.05% and ointment. At 2-week follow-up, her condition remained unchanged. Empiric systemic treatment was discussed, which would potentially work for diagnoses of both PRP and psoriasis. Due to the history of psoriasis and level of discomfort, cyclosporine 300 mg once daily was started to gain rapid control of the disease. Methotrexate also was considered due to its efficacy and economic considerations but was not selected due to patient concerns about the medication.

After 10 weeks of cyclosporine treatment, our patient showed some improvement of the skin with decreased scale and flattening of plaques but not complete resolution. At this point, a biopsy was able to be obtained with prior authorization. A 4-mm punch biopsy of the right flank demonstrated a psoriasiform and papillated epidermis with multifocally capped, compact parakeratosis and minimal lymphocytic infiltrate consistent with PRP. Although EPS also was on the histologic differential, clinical history was more consistent with a diagnosis of PRP. There was some minimal improvement with cyclosporine, but with the diagnosis of PRP confirmed, a systemic retinoid became the treatment of choice. Although acitretin is the preferred treatment for PRP, given that pregnancy would be contraindicated during and for 3 years following acitretin therapy, a trial of isotretinoin 40 mg once daily was started due to its shorter half-life compared to acitretin and was continued for 3 months (Figure 2).^6,7

The diagnosis of PRP often can be challenging given the variety of clinical presentations. This case was an atypical presentation of PRP with several learning points, as our patient’s condition did not fit perfectly into any of the 6 types of PRP. The age of onset was atypical at 22 years old. Pityriasis rubra pilaris typically presents with a bimodal age distribution, appearing either in the first decade or the fifth to sixth decades of life.^3,8 Her clinical presentation was atypical for adult-onset types I and II, which typically present with cephalocaudal progression or ichthyosiform dermatitis, respectively. Her presentation also was atypical for juvenile onset in types III, IV, and V, which tend to present in younger children and with different physical examination findings.^3,8

The morphology of our patient’s lesions also was atypical for PRP, PPK, EPS, and psoriasis. The clinical presentation had features of these entities with erythema, fissuring, xerosis, carnauba wax–like appearance, symmetric scale, and well-demarcated plaques. Although these findings are not mutually exclusive, their combined presentation is atypical. Coupled with the ambiguous family history of similar skin disease in the patient’s father, the discussion of genodermatoses, particularly PPK, further confounded the diagnosis.^4,9 When evaluating for PRP, especially with any family history of skin conditions, genodermatoses should be considered. Furthermore, our patient’s remote and unverifiable history of psoriasis serves as a cautionary reminder that prior diagnoses and medical history always should be reasonably scrutinized. Additionally, a drug-induced PRP eruption also should be considered. Although our patient received no medical treatment for the upper respiratory tract infection prior to the onset of PRP, there have been several reports of drug-induced PRP.^10-12

The therapeutic challenge in this case is one that often is encountered in clinical practice. The health care system often may pose a barrier to diagnosis by inhibiting particular services required for adequate patient care. For our patient, diagnosis was delayed by several weeks due to difficulties obtaining a diagnostic skin biopsy. When faced with challenges from health care infrastructure, creativity with treatment options, such as finding an empiric treatment option (cyclosporine in this case), must be considered.

Systemic retinoids have been found to be efficacious treatment options for PRP, but when dealing with a woman of reproductive age, reproductive preferences must be discussed before identifying an appropriate treatment regimen.^1,13-15 The half-life of acitretin compared to isotretinoin is 2 days vs 22 hours.^6,16 With alcohol consumption, acitretin can be metabolized to etretinate, which has a half-life of 120 days.¹⁷ In our patient, isotretinoin was a more manageable option to allow for greater reproductive freedom upon treatment completion.

To the Editor:

A 40-year-old Somalian man presented to the dermatology clinic with lesions on the eyelids, tongue, lips, and hands of 8 years’ duration. He was a former refugee who had faced considerable stigma from his community due to his appearance. A review of systems was remarkable for decreased appetite but no weight loss. He reported no abdominal distention, early satiety, or urinary symptoms, and he had no personal history of diabetes mellitus or obesity. Physical examination demonstrated hyperpigmented velvety plaques in all skin folds and on the genitalia. Massive papillomatosis of the eyelid margins, tongue, and lips also was noted (Figure 1A). Flesh-colored papules also were scattered across the face. Punctate, flesh-colored papules were present on the volar and palmar hands (Figure 2A). Histopathology demonstrated pronounced papillomatous epidermal hyperplasia with negative human papillomavirus (HPV) type 16 and HPV-18 DNA studies. Given the appearance of malignant acanthosis nigricans with oral and conjunctival features, cutaneous papillomatosis, and tripe palms, concern for underlying malignancy was high. Malignancy workup, including upper and lower endoscopy as well as serial computed tomography scans of the chest, abdomen, and pelvis, was unrevealing.

Laboratory investigation revealed a positive Schistosoma IgG antibody (0.38 geometric mean egg count) and peripheral eosinophilia (1.09 ×10³/μL), which normalized after praziquantel therapy. With no malignancy identified over the preceding 6-month period, treatment with acitretin 50 mg daily was initiated based on limited literature support.^1-3 Treatment led to reduction in the size and number of papillomas (Figure 1B) and tripe palms (Figure 2B) with increased mobility of hands, lips, and tongue. The patient underwent oculoplastic surgery to reduce the papilloma burden along the eyelid margins. Subsequent cystoscopy 9 months after the initial presentation revealed low-grade transitional cell carcinoma of the bladder. Intraoperative mitomycin C led to tumor shrinkage and, with continued treatment with daily acitretin, dramatic improvement of all cutaneous and mucosal symptoms (Figure 1C and Figure 2C). To date, his cutaneous symptoms have resolved.

This case demonstrated a unique presentation of multiple paraneoplastic signs in bladder transitional cell carcinoma. The presence of malignant acanthosis nigricans (including oral and conjunctival involvement), cutaneous papillomatosis, and tripe palms have been individually documented in various types of gastric malignancies.⁴ Acanthosis nigricans often is secondary to diabetes and obesity, presenting with diffuse, thickened, velvety plaques in the flexural areas. Malignant acanthosis nigricans is a rare, rapidly progressive condition that often presents over a period of weeks to months; it almost always is associated with internal malignancies. It often has more extensive involvement, extending beyond the flexural areas, than typical acanthosis nigricans.⁴ Oral involvement can be either hypertrophic or papillomatous; papillomatosis of the oral mucosa was reported in over 40% of malignant acanthosis nigricans cases (N=200).⁵ Cases with conjunctival involvement are less common.⁶ Although malignant acanthosis nigricans often is codiagnosed with a malignancy, it can precede the cancer diagnosis in some cases.^7,8 A majority of cases are associated with adenocarcinomas of the gastrointestinal tract.⁴ Progressive mucocutaneous papillomatosis also is a rare paraneoplastic condition that most commonly is associated with gastric adenocarcinomas. Progressive mucocutaneous papillomatosis often presents rapidly as verrucous growths on cutaneous surfaces (including the hands and face) but also can affect mucosal surfaces such as the mouth and conjunctiva.^9-11 Tripe palms are characterized by exaggerated dermatoglyphics with diffuse palmar ridging and hyperkeratosis. Tripe palms most often are associated with pulmonary malignancies. When tripe palms are present with malignant acanthosis nigricans, they reflect up to a one-third incidence of gastrointestinal malignancy.^12,13

Despite the individual presentation of these paraneoplastic signs in a variety of malignancies, synchronous presentation is rare. A brief literature review only identified 6 cases of concurrent acanthosis nigricans, tripe palms, and progressive mucocutaneous papillomatosis with an underlying gastrointestinal malignancy.^1,11,14-17 Two additional reports described tripe palms with oral acanthosis nigricans and progressive mucocutaneous papillomatosis in metastatic gastric adenocarcinoma and renal urothelial carcinoma.^2,18 An additional case of all 3 paraneoplastic conditions was reported in the setting of metastatic cervical cancer (HPV positive).¹⁹ Per a recent case report and literature review,²⁰ there have only been 8 cases of acanthosis nigricans reported in bladder transitional cell carcinoma,^20-27 half of which have included oral malignant acanthosis nigricans.^20-23 Only one report of concurrent cutaneous and oral malignant acanthosis nigricans and triple palms in the setting of bladder cancer has been reported.²⁰ Given the extensive conjunctival involvement and cutaneous papillomatosis in our patient, ours is a rarely reported case of concurrent malignant mucocutaneous acanthosis nigricans, tripe palms, and progressive papillomatosis in transitional cell bladder carcinoma. We believe it is imperative to consider the role of this malignancy as a cause of these paraneoplastic conditions.

Although these paraneoplastic conditions rarely co-occur, our case further offers a common molecular pathway for these conditions.²⁸ In these paraneoplastic conditions, the stimulating factor is thought to be tumor growth factor α, which is structurally related to epidermal growth factor (EGF). Epidermal growth factor receptors (EGFRs) are found in the basal layer of the epidermis, where activation stimulates keratinocyte growth and leads to the cutaneous manifestation of symptoms.²⁸ Fibroblast growth factor receptor 3 mutations are found in most noninvasive transitional cell tumors of the bladder.²⁹ The fibroblast growth factor pathway is distinctly different from the tumor growth factor α and EGF pathways.³⁰ However, this association with transitional cell carcinoma suggests that fibroblast growth factor receptor 3 also may be implicated in these paraneoplastic conditions.

Our patient responded well to treatment with acitretin 50 mg daily. The mechanism of action of retinoids involves inducing mitotic activity and desmosomal shedding.³¹ Retinoids downregulate EGFR expression and activation in EGF-stimulated cells.³² We hypothesize that these oral retinoids decreased the growth stimulus and thereby improved cutaneous signs in the setting of our patient’s transitional cell cancer. Although definitive therapy is malignancy management, our case highlights the utility of adjunctive measures such as oral retinoids and surgical debulking. While previous cases have reported use of retinoids at a lower dosage than used in this case, oral lesions often have only been mildly improved with little impact on other cutaneous symptoms.^1,2 In one case of malignant acanthosis nigricans and oral papillomatosis, isotretinoin 25 mg once every 2 to 3 days led to a moderate decrease in hyperkeratosis and papillomas, but the patient was lost to follow-up.³ Our case highlights the use of higher daily doses of oral retinoids for over 9 months, resulting in marked improvement in both the mucosal and cutaneous symptoms of acanthosis nigricans, progressive mucocutaneous papillomatosis, and tripe palms. Therefore, oral acitretin should be considered as adjuvant therapy for these paraneoplastic conditions.

By reporting this case, we hope to demonstrate the importance of considering other forms of malignancies in the presence of paraneoplastic conditions. Although gastric malignancies more commonly are associated with these conditions, bladder carcinomas also can present with cutaneous manifestations. The presence of these paraneoplastic conditions alone or together rarely is reported in urologic cancers and generally is considered to be an indicator of poor prognosis. Paraneoplastic conditions often develop rapidly and occur in very advanced malignancies.⁴ The disfiguring presentation in our case also had unusual diagnostic challenges. The presence of these conditions for 8 years and nonmetastatic advanced malignancy suggest a more indolent process and that these signs are not always an indicator of poor prognosis. Future patients with these paraneoplastic conditions may benefit from both a thorough malignancy screen, including cystoscopy, and high daily doses of oral retinoids.

To the Editor:

A 40-year-old Somalian man presented to the dermatology clinic with lesions on the eyelids, tongue, lips, and hands of 8 years’ duration. He was a former refugee who had faced considerable stigma from his community due to his appearance. A review of systems was remarkable for decreased appetite but no weight loss. He reported no abdominal distention, early satiety, or urinary symptoms, and he had no personal history of diabetes mellitus or obesity. Physical examination demonstrated hyperpigmented velvety plaques in all skin folds and on the genitalia. Massive papillomatosis of the eyelid margins, tongue, and lips also was noted (Figure 1A). Flesh-colored papules also were scattered across the face. Punctate, flesh-colored papules were present on the volar and palmar hands (Figure 2A). Histopathology demonstrated pronounced papillomatous epidermal hyperplasia with negative human papillomavirus (HPV) type 16 and HPV-18 DNA studies. Given the appearance of malignant acanthosis nigricans with oral and conjunctival features, cutaneous papillomatosis, and tripe palms, concern for underlying malignancy was high. Malignancy workup, including upper and lower endoscopy as well as serial computed tomography scans of the chest, abdomen, and pelvis, was unrevealing.

Laboratory investigation revealed a positive Schistosoma IgG antibody (0.38 geometric mean egg count) and peripheral eosinophilia (1.09 ×10³/μL), which normalized after praziquantel therapy. With no malignancy identified over the preceding 6-month period, treatment with acitretin 50 mg daily was initiated based on limited literature support.^1-3 Treatment led to reduction in the size and number of papillomas (Figure 1B) and tripe palms (Figure 2B) with increased mobility of hands, lips, and tongue. The patient underwent oculoplastic surgery to reduce the papilloma burden along the eyelid margins. Subsequent cystoscopy 9 months after the initial presentation revealed low-grade transitional cell carcinoma of the bladder. Intraoperative mitomycin C led to tumor shrinkage and, with continued treatment with daily acitretin, dramatic improvement of all cutaneous and mucosal symptoms (Figure 1C and Figure 2C). To date, his cutaneous symptoms have resolved.

This case demonstrated a unique presentation of multiple paraneoplastic signs in bladder transitional cell carcinoma. The presence of malignant acanthosis nigricans (including oral and conjunctival involvement), cutaneous papillomatosis, and tripe palms have been individually documented in various types of gastric malignancies.⁴ Acanthosis nigricans often is secondary to diabetes and obesity, presenting with diffuse, thickened, velvety plaques in the flexural areas. Malignant acanthosis nigricans is a rare, rapidly progressive condition that often presents over a period of weeks to months; it almost always is associated with internal malignancies. It often has more extensive involvement, extending beyond the flexural areas, than typical acanthosis nigricans.⁴ Oral involvement can be either hypertrophic or papillomatous; papillomatosis of the oral mucosa was reported in over 40% of malignant acanthosis nigricans cases (N=200).⁵ Cases with conjunctival involvement are less common.⁶ Although malignant acanthosis nigricans often is codiagnosed with a malignancy, it can precede the cancer diagnosis in some cases.^7,8 A majority of cases are associated with adenocarcinomas of the gastrointestinal tract.⁴ Progressive mucocutaneous papillomatosis also is a rare paraneoplastic condition that most commonly is associated with gastric adenocarcinomas. Progressive mucocutaneous papillomatosis often presents rapidly as verrucous growths on cutaneous surfaces (including the hands and face) but also can affect mucosal surfaces such as the mouth and conjunctiva.^9-11 Tripe palms are characterized by exaggerated dermatoglyphics with diffuse palmar ridging and hyperkeratosis. Tripe palms most often are associated with pulmonary malignancies. When tripe palms are present with malignant acanthosis nigricans, they reflect up to a one-third incidence of gastrointestinal malignancy.^12,13

Despite the individual presentation of these paraneoplastic signs in a variety of malignancies, synchronous presentation is rare. A brief literature review only identified 6 cases of concurrent acanthosis nigricans, tripe palms, and progressive mucocutaneous papillomatosis with an underlying gastrointestinal malignancy.^1,11,14-17 Two additional reports described tripe palms with oral acanthosis nigricans and progressive mucocutaneous papillomatosis in metastatic gastric adenocarcinoma and renal urothelial carcinoma.^2,18 An additional case of all 3 paraneoplastic conditions was reported in the setting of metastatic cervical cancer (HPV positive).¹⁹ Per a recent case report and literature review,²⁰ there have only been 8 cases of acanthosis nigricans reported in bladder transitional cell carcinoma,^20-27 half of which have included oral malignant acanthosis nigricans.^20-23 Only one report of concurrent cutaneous and oral malignant acanthosis nigricans and triple palms in the setting of bladder cancer has been reported.²⁰ Given the extensive conjunctival involvement and cutaneous papillomatosis in our patient, ours is a rarely reported case of concurrent malignant mucocutaneous acanthosis nigricans, tripe palms, and progressive papillomatosis in transitional cell bladder carcinoma. We believe it is imperative to consider the role of this malignancy as a cause of these paraneoplastic conditions.

Although these paraneoplastic conditions rarely co-occur, our case further offers a common molecular pathway for these conditions.²⁸ In these paraneoplastic conditions, the stimulating factor is thought to be tumor growth factor α, which is structurally related to epidermal growth factor (EGF). Epidermal growth factor receptors (EGFRs) are found in the basal layer of the epidermis, where activation stimulates keratinocyte growth and leads to the cutaneous manifestation of symptoms.²⁸ Fibroblast growth factor receptor 3 mutations are found in most noninvasive transitional cell tumors of the bladder.²⁹ The fibroblast growth factor pathway is distinctly different from the tumor growth factor α and EGF pathways.³⁰ However, this association with transitional cell carcinoma suggests that fibroblast growth factor receptor 3 also may be implicated in these paraneoplastic conditions.

Our patient responded well to treatment with acitretin 50 mg daily. The mechanism of action of retinoids involves inducing mitotic activity and desmosomal shedding.³¹ Retinoids downregulate EGFR expression and activation in EGF-stimulated cells.³² We hypothesize that these oral retinoids decreased the growth stimulus and thereby improved cutaneous signs in the setting of our patient’s transitional cell cancer. Although definitive therapy is malignancy management, our case highlights the utility of adjunctive measures such as oral retinoids and surgical debulking. While previous cases have reported use of retinoids at a lower dosage than used in this case, oral lesions often have only been mildly improved with little impact on other cutaneous symptoms.^1,2 In one case of malignant acanthosis nigricans and oral papillomatosis, isotretinoin 25 mg once every 2 to 3 days led to a moderate decrease in hyperkeratosis and papillomas, but the patient was lost to follow-up.³ Our case highlights the use of higher daily doses of oral retinoids for over 9 months, resulting in marked improvement in both the mucosal and cutaneous symptoms of acanthosis nigricans, progressive mucocutaneous papillomatosis, and tripe palms. Therefore, oral acitretin should be considered as adjuvant therapy for these paraneoplastic conditions.

By reporting this case, we hope to demonstrate the importance of considering other forms of malignancies in the presence of paraneoplastic conditions. Although gastric malignancies more commonly are associated with these conditions, bladder carcinomas also can present with cutaneous manifestations. The presence of these paraneoplastic conditions alone or together rarely is reported in urologic cancers and generally is considered to be an indicator of poor prognosis. Paraneoplastic conditions often develop rapidly and occur in very advanced malignancies.⁴ The disfiguring presentation in our case also had unusual diagnostic challenges. The presence of these conditions for 8 years and nonmetastatic advanced malignancy suggest a more indolent process and that these signs are not always an indicator of poor prognosis. Future patients with these paraneoplastic conditions may benefit from both a thorough malignancy screen, including cystoscopy, and high daily doses of oral retinoids.

To the Editor:

A 40-year-old Somalian man presented to the dermatology clinic with lesions on the eyelids, tongue, lips, and hands of 8 years’ duration. He was a former refugee who had faced considerable stigma from his community due to his appearance. A review of systems was remarkable for decreased appetite but no weight loss. He reported no abdominal distention, early satiety, or urinary symptoms, and he had no personal history of diabetes mellitus or obesity. Physical examination demonstrated hyperpigmented velvety plaques in all skin folds and on the genitalia. Massive papillomatosis of the eyelid margins, tongue, and lips also was noted (Figure 1A). Flesh-colored papules also were scattered across the face. Punctate, flesh-colored papules were present on the volar and palmar hands (Figure 2A). Histopathology demonstrated pronounced papillomatous epidermal hyperplasia with negative human papillomavirus (HPV) type 16 and HPV-18 DNA studies. Given the appearance of malignant acanthosis nigricans with oral and conjunctival features, cutaneous papillomatosis, and tripe palms, concern for underlying malignancy was high. Malignancy workup, including upper and lower endoscopy as well as serial computed tomography scans of the chest, abdomen, and pelvis, was unrevealing.

Laboratory investigation revealed a positive Schistosoma IgG antibody (0.38 geometric mean egg count) and peripheral eosinophilia (1.09 ×10³/μL), which normalized after praziquantel therapy. With no malignancy identified over the preceding 6-month period, treatment with acitretin 50 mg daily was initiated based on limited literature support.^1-3 Treatment led to reduction in the size and number of papillomas (Figure 1B) and tripe palms (Figure 2B) with increased mobility of hands, lips, and tongue. The patient underwent oculoplastic surgery to reduce the papilloma burden along the eyelid margins. Subsequent cystoscopy 9 months after the initial presentation revealed low-grade transitional cell carcinoma of the bladder. Intraoperative mitomycin C led to tumor shrinkage and, with continued treatment with daily acitretin, dramatic improvement of all cutaneous and mucosal symptoms (Figure 1C and Figure 2C). To date, his cutaneous symptoms have resolved.

This case demonstrated a unique presentation of multiple paraneoplastic signs in bladder transitional cell carcinoma. The presence of malignant acanthosis nigricans (including oral and conjunctival involvement), cutaneous papillomatosis, and tripe palms have been individually documented in various types of gastric malignancies.⁴ Acanthosis nigricans often is secondary to diabetes and obesity, presenting with diffuse, thickened, velvety plaques in the flexural areas. Malignant acanthosis nigricans is a rare, rapidly progressive condition that often presents over a period of weeks to months; it almost always is associated with internal malignancies. It often has more extensive involvement, extending beyond the flexural areas, than typical acanthosis nigricans.⁴ Oral involvement can be either hypertrophic or papillomatous; papillomatosis of the oral mucosa was reported in over 40% of malignant acanthosis nigricans cases (N=200).⁵ Cases with conjunctival involvement are less common.⁶ Although malignant acanthosis nigricans often is codiagnosed with a malignancy, it can precede the cancer diagnosis in some cases.^7,8 A majority of cases are associated with adenocarcinomas of the gastrointestinal tract.⁴ Progressive mucocutaneous papillomatosis also is a rare paraneoplastic condition that most commonly is associated with gastric adenocarcinomas. Progressive mucocutaneous papillomatosis often presents rapidly as verrucous growths on cutaneous surfaces (including the hands and face) but also can affect mucosal surfaces such as the mouth and conjunctiva.^9-11 Tripe palms are characterized by exaggerated dermatoglyphics with diffuse palmar ridging and hyperkeratosis. Tripe palms most often are associated with pulmonary malignancies. When tripe palms are present with malignant acanthosis nigricans, they reflect up to a one-third incidence of gastrointestinal malignancy.^12,13

Despite the individual presentation of these paraneoplastic signs in a variety of malignancies, synchronous presentation is rare. A brief literature review only identified 6 cases of concurrent acanthosis nigricans, tripe palms, and progressive mucocutaneous papillomatosis with an underlying gastrointestinal malignancy.^1,11,14-17 Two additional reports described tripe palms with oral acanthosis nigricans and progressive mucocutaneous papillomatosis in metastatic gastric adenocarcinoma and renal urothelial carcinoma.^2,18 An additional case of all 3 paraneoplastic conditions was reported in the setting of metastatic cervical cancer (HPV positive).¹⁹ Per a recent case report and literature review,²⁰ there have only been 8 cases of acanthosis nigricans reported in bladder transitional cell carcinoma,^20-27 half of which have included oral malignant acanthosis nigricans.^20-23 Only one report of concurrent cutaneous and oral malignant acanthosis nigricans and triple palms in the setting of bladder cancer has been reported.²⁰ Given the extensive conjunctival involvement and cutaneous papillomatosis in our patient, ours is a rarely reported case of concurrent malignant mucocutaneous acanthosis nigricans, tripe palms, and progressive papillomatosis in transitional cell bladder carcinoma. We believe it is imperative to consider the role of this malignancy as a cause of these paraneoplastic conditions.

Although these paraneoplastic conditions rarely co-occur, our case further offers a common molecular pathway for these conditions.²⁸ In these paraneoplastic conditions, the stimulating factor is thought to be tumor growth factor α, which is structurally related to epidermal growth factor (EGF). Epidermal growth factor receptors (EGFRs) are found in the basal layer of the epidermis, where activation stimulates keratinocyte growth and leads to the cutaneous manifestation of symptoms.²⁸ Fibroblast growth factor receptor 3 mutations are found in most noninvasive transitional cell tumors of the bladder.²⁹ The fibroblast growth factor pathway is distinctly different from the tumor growth factor α and EGF pathways.³⁰ However, this association with transitional cell carcinoma suggests that fibroblast growth factor receptor 3 also may be implicated in these paraneoplastic conditions.

Our patient responded well to treatment with acitretin 50 mg daily. The mechanism of action of retinoids involves inducing mitotic activity and desmosomal shedding.³¹ Retinoids downregulate EGFR expression and activation in EGF-stimulated cells.³² We hypothesize that these oral retinoids decreased the growth stimulus and thereby improved cutaneous signs in the setting of our patient’s transitional cell cancer. Although definitive therapy is malignancy management, our case highlights the utility of adjunctive measures such as oral retinoids and surgical debulking. While previous cases have reported use of retinoids at a lower dosage than used in this case, oral lesions often have only been mildly improved with little impact on other cutaneous symptoms.^1,2 In one case of malignant acanthosis nigricans and oral papillomatosis, isotretinoin 25 mg once every 2 to 3 days led to a moderate decrease in hyperkeratosis and papillomas, but the patient was lost to follow-up.³ Our case highlights the use of higher daily doses of oral retinoids for over 9 months, resulting in marked improvement in both the mucosal and cutaneous symptoms of acanthosis nigricans, progressive mucocutaneous papillomatosis, and tripe palms. Therefore, oral acitretin should be considered as adjuvant therapy for these paraneoplastic conditions.

By reporting this case, we hope to demonstrate the importance of considering other forms of malignancies in the presence of paraneoplastic conditions. Although gastric malignancies more commonly are associated with these conditions, bladder carcinomas also can present with cutaneous manifestations. The presence of these paraneoplastic conditions alone or together rarely is reported in urologic cancers and generally is considered to be an indicator of poor prognosis. Paraneoplastic conditions often develop rapidly and occur in very advanced malignancies.⁴ The disfiguring presentation in our case also had unusual diagnostic challenges. The presence of these conditions for 8 years and nonmetastatic advanced malignancy suggest a more indolent process and that these signs are not always an indicator of poor prognosis. Future patients with these paraneoplastic conditions may benefit from both a thorough malignancy screen, including cystoscopy, and high daily doses of oral retinoids.