Communication vital in diagnosing adults with food allergies
Click Here to Manage Email Alerts
SAN ANTONIO — Although data are sparse, management strategies for children with food allergies often can be applied to adults, according to a presentation at the American Academy of Allergy, Asthma & Immunology Annual Meeting.
This treatment depends on communication between the patient and provider, which may influence oral food challenges in this population, Andrea A. Pappalardo, MD, assistant professor of medicine and pediatrics at University of Illinois at Chicago, said during her presentation.
“Believe the patient,” Pappalardo said before offering two case studies illustrating how adult food allergy may be addressed.
Case one
The first patient was a Black woman aged 22 years with a history of severe, persistent asthma, previous intubation, chronic rhinosinusitis and multiple stays in a pediatric hospital for asthma exacerbations. During her most recent hospital admission, when she was aged approximately 18 years, she reported anaphylaxis due to a lemon allergy.
“At that time, no one believed her that she could possibly have anaphylaxis to lemon,” Pappalardo said.
The providers at the hospital told her that they would conduct an OFC by giving her a lemon ice.
“The food challenge did not go well,” Pappalardo said, adding that she developed anaphylaxis and needed two doses of epinephrine via autoinjector.
“She became extraordinarily scared to eat anything thereafter,” Pappalardo continued. “Having that experience was quite traumatic for her, especially when she was in what was previously considered a safe space.”
The hospital then referred the patient to Pappalardo.
“I first and foremost took a step back and said, ‘Oh my God. I can’t believe that happened to you. I’m so sorry. Let’s move forward and work on your allergies and break them down problem by problem together,’” Pappalardo said.
Pappalardo consulted the patient’s records, which documented the systemic reaction to the lemon ice. The patient’s tryptase was normal before the reaction, but the hospital did not measure it afterward. Also, the patient’s specific IgE was normal.
The hospital did not conduct any skin prick testing, but Pappalardo attributed this to the medications the patient already was receiving, which would have interfered with that testing.
“The reality is that many of the primary care providers who are taking care of food allergies in adults are frequently scared of it and have no idea what to do,” Pappalardo said. “In adults, they’re sending anything over, and you just have to sort through the madness.”
The patient is now doing well by avoiding lemon, Pappalardo said. No repeat OFCs are planned. Also, Pappalardo said, the patient is experiencing better control over her asthma by avoiding allergenic foods and sticking to guideline-based asthma treatments.
A different approach
“What we really need to recognize is that food allergy does occur in adults. It can be new onset,” Pappalardo said. “We have to talk about it in a different way.”
Pappalardo said providers can be skeptical when they see adult patients who say they have a food allergy, because many people believe they do have a food allergy when they really do not. Overall, she continued, 10.8% of adults have a food allergy.
Food intolerance and gastrointestinal symptoms often can be mistaken for food allergy, Pappalardo said, but the opposite may be true too.
“This person might actually have a severe food allergy. It may be IgE-mediated. It might not be. But we have to believe them, too, and we have to understand that we are basing data on adults with information we really don’t know,” she said.
Pappalardo recommended an algorithm developed by Gupta et al that queries patients about symptoms, histories and previous diagnoses before deeming a suspected food allergy a severe convincing food allergy.
Complicating the issue, Pappalardo continued, anaphylaxis does not have to be mediated by IgE. Also, other mechanisms may trigger mast and other immune cells to trigger a seemingly indistinguishable presentation of anaphylaxis. Patients may lack specific IgE and/or tryptase elevations associated with anaphylaxis as well.
Or tryptase may be elevated even if it is not mediated by IgE. Similarly, even though specific IgE and a SPT may indicate that things are fine, they might not be, Pappalardo explained.
“I think that this is what we’re seeing in some of these atypical foods, and we’re seeing this more commonly,” Pappalardo said. “We have to think about this potential.”
When patients are experiencing severe reactions but the testing does not add up, Pappalardo said, OFCs may be necessary, but they require shared decision making. Otherwise, outcomes may be frustrating.
“A lot of the times, you do a challenge and they pass, and then they won’t even put it in their diet. Like, what was the point?” she asked. “That was 2 and a half hours. But you have to talk about it beforehand.”
For example, the young woman with the lemon allergy felt like she was being forced into the OFC.
“That discussion never occurred. She was young, and she was not confident enough in herself, and she recognizes this and has since gained the confidence that she can say no,” Pappalardo said. “If you want to do a challenge with an adult, you have to talk to them.”
Pappalardo cautioned, however, that patients with asthma or other allergies will have higher reaction rates and will be more likely to have a true food allergy.
Many adults fail to reintroduce foods into their diets due to atypical symptoms, Pappalardo said, and fear is a large factor. Education may help patients overcome these fears, she continued, but if patients do not like the food, then the OFC is not worth doing.
Case two
Calling it a case of oral allergy syndrome (OAS) “gone wild,” Pappalardo described a woman aged 48 years of Asian ancestry who came to her for evaluation of allergic rhinitis and mild, persistent asthma, in addition to multiple food allergies.
“Her food allergy list was long and exhaustive,” Pappalardo said, including classic anaphylaxis for shellfish and palatal itching and feelings of closure in her esophagus for a variety of fruits, vegetables, spices and other foodstuffs.
Diagnosed with OAS, the patient had started subcutaneous immunotherapy but discontinued treatment after multiple bouts of anaphylaxis. COVID-19 then followed.
“After COVID, every single food that she reacted to in OAS almost became anaphylaxis,” Pappalardo said. “It was crazy. She couldn’t breathe.”
All the testing was negative, except for the C1q antibody, prompting Pappalardo to suspect a lipid transfer protein allergy.
“Maybe this was a viral cofactor of some sort where COVID just unleashed this inflammatory monster on this woman,” Pappalardo said, adding that the patient had to quit her job and her master’s program.
The patient began a course of omalizumab and began to improve. Every month or two, she reintroduced more foods into her diet. After a few years of this treatment, the patient could tolerate almost all those foods that previously caused reactions.
Takeaways for clinicians
These cases indicate how food allergies are not well defined or understood in adults, Pappalardo said, although evidence-based practices for food allergy management in children often can be applied to adults.
Also, Pappalardo cautioned that anaphylaxis that is not mediated by IgE may be more prevalent and should be considered more frequently. Atypical symptoms may occur during OFCs for adults as well, but education and communication can improve reintroduction rates.
“You really need to work with the individual,” Pappalardo said. “If they don’t want the food, don’t bother. If they do want the food, work with them to calm them and be ready so that they can have a successful oral food challenge.”
Finally, Pappalardo called for additional studies of sensitization patterns in adults with food allergies and of treatment modalities designed to help adults with food allergy manage their disease and improve their quality of life.