Reliability of banana-specific ige testing prior to oral food challenge

IntroductionAllergy to direct fruit is relatively rare, and when present is commonly associated with fruits such as kiwi and avocado. True IgE-mediated allergy to banana is uncommonly reported in the literature, as is data regarding the reliability of specific IgE testing prior to oral food challenge (OFC).MethodsRetrospective chart review was performed on six patients with purported banana allergy who underwent banana-specific IgE testing prior to banana OFC. Their charts were reviewed for demographic data, banana-specific IgE testing, total IgE testing, other food allergies, atopic conditions, and banana OFC results.ResultsAll six patients were found to have a history of atopic conditions and other food allergies. Two of the six patients failed their OFC, and the remaining four patients passed. The primary symptom(s) reported at initial ingestion was emesis for the patients who failed versus hives/rash and facial swelling for those who passed. Average banana-specific IgE for patients who failed OFC=1.56 (SD:1.12 N=2), patients who passed OFC=3.13 (SD:3.65 N=4), and all patients=2.60 (SD:2.98 N=6).ConclusionThis study finds that elevated banana-specific IgE is likely not a reliable pre-test predictor for OFC failure. In our study sample, average banana-specific IgE was higher in patients who passed OFC than in those who failed. However, symptomatology may provide better predictive value given that the patients who failed OFC both had emesis with initial banana exposure versus dermatologic symptoms in patients who passed OFC.