Clinical Characteristics of Peanut Allergic Patients in a Midwest, Suburban-Based, Private Allergy Practice

Abstract

Clinical characteristics of peanut allergic patients may vary based on the population studied; they are understudied in private, community-based practices. Records of possible peanut allergic patients (clear reaction history or sensitization without a reaction history) undergoing challenges were reviewed. Of 39 patients (27 male; median age 79 months) undergoing a peanut open oral challenge (pOC), 14 had a prior clinical reaction (11 skin, 2 GI, 1 skin and lower respiratory) while 25 were avoiding peanut based on sensitization alone. The mean peanut skin prick test wheal (pSPT) was 7 mm; the mean peanut IgE (pIgE) was 7.05 kU/L. Eight patients failed the pOC; 4 with a previous clinical history. Median pSPT/pIgE in those patients who passed were 5 mm / 0.72 kU/L versus those who failed 10/1.6. pSPT > 9 mm was more likely to occur in patients who failed (n=4) versus passed (n=3) pOC (p=0.0099) Logistic regression revealed increasing wheal size was a predictor of oral peanut challenge outcome (p=0.024). Five patients who passed the pOC had pIgE >5 kU/L but no previous reaction history. Correlation between pSPT and pIgE was 0.087 (p=0.597). The predictive values of pSPT and pIgE for clinical peanut allergy in a community based practice likely differ from those published by academic medical centers. pSPT > 9 mm is associated with a failed challenge.