With degrees in electrical engineering and computer science from the Massachusetts Institute of Technology, Nikhila Schroeder, MD, MEng, brings a problem-solving mindset to medicine.
Being a doctor means having to “figure out all aspects of [a patient’s] situation and do my best to come up with an answer,” said Dr. Schroeder, who founded Allergenuity Health, a solo allergy practice in Huntersville, N.C., with her husband James, who serves as practice executive. It’s “being a medical detective for your patient.”
Yet, during her training, Dr. Schroeder found that market-driven health care makes it hard to practice medicine with a patient’s best interest foremost. Procedures for diagnosing and treating disease cater to insurance companies’ reimbursement policies. “You wind up having to tailor your care to whatever insurance will cover,” she said.
Insurers, in turn, look for evidence from large, peer-reviewed studies to prove that a treatment works. Many physicians hesitate to offer therapies that aren’t covered by insurance, for both liability and financial reasons. So treatment tends to be limited to those options that were rigorously vetted in long, costly, multisite trials that are difficult to conduct without a corporate sponsor.
This is why there is still only one licensed treatment for people with food allergies – a set of standardized peanut powder capsules (Palforzia) that was approved by the Food and Drug Administration in early 2020 for peanut-allergic children aged 4-17 years. A small but growing number of allergists offer unapproved oral immunotherapy (OIT) using commercial food products to treat allergies to peanuts and other foods.
Even fewer allergists treat food allergy patients with another immune-modifying treatment, sublingual immunotherapy (SLIT), which delivers allergens through liquid drops held for several minutes under the tongue. Since 2018, Allergenuity Health, which offers SLIT to treat food and environmental allergies, has provided care to more than 400 patients. More than a third have come from out of state.
The clinic uses a direct-care approach. Rather than taking insurance, the clinic offers a monthly billing program that includes tests, SLIT bottles, and access to Dr. Schroeder via phone, email, or text. “I’m only contracted with the patient, and my only focus is the patient,” Dr. Schroeder said in an interview.
Allergy was not on Dr. Schroeder’s radar in medical school. She wanted to be a surgeon. But she loved working with children, so she did a pediatrics residency at the University of Virginia Children’s Hospital in Charlottesville. There Dr. Schroeder started seeing kids with eczema and allergies. While covering a friend’s clinic shift in 2010, she was thrust into an emergency. A family who didn’t speak English had just brought in their screaming 6-month-old baby, red and puffy with hives. “We didn’t know what was going on with this child,” Dr. Schroeder said. “Somehow I was elected to go in there.”
All of a sudden, things got quiet. Yet the baby was still screaming, mouth wide open. Dr. Schroeder had learned about anaphylaxis but had never witnessed it – until that day. The baby›s airways swelled so much that the crying became hoarse and soft. After working with a nurse to administer epinephrine, Dr. Schroeder saw something equally unforgettable: The baby’s heart rate soared, but within minutes the hives and swelling subsided and smiles returned. “It was incredible how quickly things changed,” Dr. Schroeder said. The baby had a reaction to rice, an uncommon allergen.
Dr. Schroeder stayed at UVA 2 more years to complete an allergy and immunology fellowship. She learned to diagnose food allergies but became frustrated having to tell patients they had little recourse but to avoid the food and to check in every year or 2. “I was, like, aren’t we specialists? Shouldn’t we have a little more expertise and maybe see if there are ways we could change this?” Dr. Schroeder said.
During those years, allergy shots were the only form of immunotherapy being taught to fellows. At clinic, Dr. Schroeder served as backup to the nurses when someone reacted to shots. She was troubled that some patients needed epinephrine to stop asthma attacks caused by injections they had received as treatment. The idea of injecting substances under the skin seemed akin to vaccination – where “you want to aggravate the immune system, you want it to get revved up, you want to build it up to fight,” she said. “But that’s not what you want for allergy. You want to tone it down. It didn’t really, to be honest, make a lot of sense to me.”
Dr. Schroeder started digging and asking questions. How does the immune system decide what is safe? Which cells and molecules communicate these decisions? She thought about babies and how they “learn” by putting stuff into their mouths. “If we don’t tolerate most of what we take in there, we wouldn’t survive,” Dr. Schroeder said. “It makes a lot of sense that a lot of tolerance begins with cells of the mouth.”
Dr. Schroeder discussed these concepts with her attendings. “They were all, like, no, there’s really no good evidence for that,” she said. But at some point, someone mentioned sublingual immunotherapy, and Schroeder came across Allergy Associates of La Crosse (Wis.).
The clinic’s late founder, David Morris, MD, learned about SLIT in the 1960s as an alternative option for farmers who suffered terrible side effects from injection immunotherapy they received to treat their mold allergies. Dr. Morris attended conferences, learned more about sublingual techniques – at times seeking advice from European allergists who offered SLIT – and became board certified in allergy before opening the La Crosse clinic in 1970. According to the clinic, more than 200,000 patients with environmental and food allergies have been treated with its SLIT protocol.
Dr. Schroeder was shocked to discover that this clinic had existed for 40 years, yet “I, as an allergist, had heard nothing about them,” she said.
Toward the end of her fellowship, OIT was becoming more well known. But she felt its risks were often downplayed. After years of talking with food allergy patients, Schroeder realized that most didn’t actually care about eating peanut butter sandwiches or sesame or walnuts. “Often I would hear, through tears: ‘I just want my child to be able to sit with their friends at lunch, to not be put at this other table, to not feel so isolated,’ ” she said. What mattered most to many families was gaining enough protection to not feel anxious about participating in social activities involving food.
Dr. Schroeder had a growing sense that SLIT – given its ease, safety, and sensible route of allergen delivery – seemed more useful. She wanted to learn more.
Her mentors urged her to stay in academia instead. “They were, like, you have a good academic reputation. You’re a solid thinker. You’re great at what you do. Do the traditional stuff,” Dr. Schroeder said.
Despite these admonitions, Dr. Schroeder left academia and took a job at La Crosse after completing her allergy fellowship. Determined to see whether SLIT could be effective, “I decided in the end, you know what, I have to go do this,” she said. “I need to know, and the only way I’m going to know is to do it, because no one was giving me good information.”
Before treating anyone with SLIT, Dr. Schroeder tried it herself – as a La Crosse patient. Growing up with severe eczema, eye swelling, and chronic nasal congestion leading to sinus infections, “I myself was a severely allergic person,” she said. Within several months, Dr. Schroeder saw dramatic improvement in her symptoms – “a night and day difference.” She experienced some mouth tingling, one of SLIT’s most common side effects, but found it “very tolerable, very mild.”
Allergenuity Health doesn’t aim to promote SLIT as the best treatment, said Dr. Schroeder, who has helped some families use avoidance or OIT as a better option. “An initial evaluation is always about proper diagnosis and education about all the treatment options available. Really, the point is education – be a detective for them and figure out what’s going on, be honest about what we know and what we don’t know, and give them the tools to figure out how to proceed.”