Analysis of Oral Food Challenges for Almond Hypersensitivity
Sunday, March 6, 2016
South Exhibit Hall H (Convention Center)
Paul E. Hesterberg, MD, Yamini Virkud, MD, MA, MPH, Caroline Southwick, Alexandra R. Alejos, BA, Elisabeth S. Stieb, RN BSN AE-C, Wayne Shreffler, MD PhD FAAAAI

Rationale:  The utility of clinical testing or history of prior reaction to predict IgE-mediated almond hypersensitivity is unknown. This was assessed by evaluating oral food challenge (OFC) outcomes performed to almond in a clinical setting.

Methods:  242 open OFCs were analyzed from the MGHfC OFC Database in 239 patients, ages 11 months to 55 years (median age 7.6 years).  Nursing flow and symptom score sheets were reviewed to evaluate subjective and objective signs and symptoms during challenges. 

Results: Median almond IgE was 0.6kU/L (range: <0.35, 81.9) and median skin prick test (SPT) was 3mm (range: 0, 15). Fifty-nine subjects (25%) had both negative skin testing and serum IgE to almond (double negative). Sixteen subjects had a history of prior reaction to almond. OFC outcomes included 223 passes (92%), 13 (5%) failures, and 6 (3%) indeterminate. Among challenge failures, median IgE to almond was 0.41kU/L (6 with negative IgE), and median SPT was 5mm (3 with negative SPTs). When comparing challenge passes to failures, there was no statistical difference based on prior history of almond reaction (6.7% of passes vs 7.7% of fails), or presence of almond sensitization (75% of passes vs 77% of fails). Ten of 13 challenge failures (77%) received antihistamines alone for treatment. No subjects received intramuscular epinephrine. Symptoms were mild in all patients with cutaneous symptoms (flushing, mild urticaria, pruritus) predominant.  

Conclusions: In this cohort, neither almond sensitization nor prior history of almond reaction was predictive of challenge failure. Additionally, reactions during almond challenge are rare and mild in severity.