299 - Clinical Insights into Allergen-Specific Symptom Profiles in Oral Immunotherapy

Publication Number: 2289.299

Eirene Fithian, Weill Cornell Medicine, New York, NY, United States; Allison Anderson, Latitude Food Allergy Care, Seattle, WA, United States; Samuel Shrank, Latitude Food Allergy Care, Boulder, CO, United States; Zahida Rani C. Maskatia, Latitude Food Allergy Care, Redwood City, CA, United States; Charlene Thomas, Weill Cornell Medicine, New York, NY, United States; Perdita Permaul, Weill Cornell Medicine, New York, NY, United States; Priya Katari, Weill Cornell, New York, NY, United States

Background: Food allergy affects approximately 8% of children and 10% of adults in the United States. Oral immunotherapy (OIT) has emerged as a promising treatment to raise reaction thresholds but is associated with treatment-related reactions. Different allergens elicit distinct symptoms during allergic reactions, yet data on how these patterns manifest during OIT in clinical practice is limited, especially for less common allergens.

Objective: To characterize how symptom profiles during OIT vary by allergen to inform patient counseling and risk discussions.

Design/Methods: A retrospective cohort study was conducted with clinical data from 1,003 patients (ages 0-47 years) undergoing OIT at Latitude Food Allergy Care from 2018-2024. OIT-related reactions were reviewed, categorized by symptom type and severity using a modified CoFAR v3 scale, and stratified by 29 allergens.

Results: The most common symptoms were pruritus (36.3%), mild abdominal pain (33.7%), and emesis or diarrhea (22.4%) (Figure 1). Milk and egg were associated with the highest overall reaction incidence.

Milk OIT was associated with higher incidence of emesis or diarrhea (36.4%, 95% CI 28–46), hives (16.4%, 95% CI 10–25), and respiratory symptoms including sniffling or sneezing (19.1%, 95% CI 12–28), frequent cough (12.7%, 95% CI 7.4–21), and severe congestion (8.2%, 95% CI 4.0–15), compared with overall cohort means of 22.4% (95% CI 20–25), 6.9% (95% CI 5.5–8.8), 9.4% (95% CI 7.7–11), 4.7% (95% CI 3.3–6.0), and 2.3% (95% CI 1.5–3.5), respectively. Egg OIT similarly demonstrated elevated incidence of emesis or diarrhea (35.4%, 95% CI 28–44) and sniffling/sneezing (17.0%, 95% CI 12–24) relative to cohort means. Pruritus, mild abdominal pain, redness, cough, and dyspnea showed no significant variation across peanut, tree nut, milk, egg, and sesame (Figure 2).

Among less common allergens, notable patterns included chest tightening (8.3%) and moderate-to-severe abdominal pain (25%) with Brazil nut; mild abdominal pain (52.6%) with pine nut; throat and chest tightness (11.1% each) with mustard; dyspnea and lip swelling (12.5% each) with soy; dyspnea and eczema flare (14.7% each) with wheat; and higher incidence of eczema or redness (16.7% each) but lower incidence of emesis or diarrhea (8.3%) with shrimp.

Conclusion(s): This study characterized symptom differences during OIT across allergens, with milk and egg demonstrating more clinically significant reaction profiles, driven primarily by gastrointestinal symptoms. Further work should examine modifiers such as age and baseline allergy severity.

Figure 1: Distribution of reaction types during oral immunotherapy (OIT).
Figure 1.pdfBars represent the mean prevalence of each symptom category among reported reactions, with error bars indicating 95% confidence intervals.

Figure 2: Symptom distribution of oral immunotherapy (OIT) reactions stratified by allergen.
Figure 2.pdfEach panel displays the mean prevalence of symptom categories among reactions to a specific allergen, with error bars indicating 95% confidence intervals.