Routine elective penicillin allergy skin testing in children and adolescents: study of sensitization

This study aims at evaluating the possibility in children and adolescents of (re)sensitization to penicillin that could result from skin test and challenge. Patients (240) with a history of a reaction to penicillin or one of its analogs were skin-tested with penicillin G, commerical benzlpenicilloyl polylysine, and a minor determinant mixture consisting of sodium benzylpenicilloate and sodium benzylpenilloate. The patients were tested when well, in no immediate need for penicillin, and during a routine office visit. Twenty-one (8.75%) patients had one or more positive skin tests. Three (14%) of the positive reactors reacted only to the MDM mixture, with one reacting only to the benzylpenilloate component. Of the patients with negative skin tests, 219 were given a 10-day course of oral penicillin. Three (1.4%) of the patients developed a-mild skin exanthem 7 to 10 days after starting the penicillin. All skin test-negative patients were retested 4 wk or more after completion of the oral challenge. Only two patients (less than 1%) who tolerated an oral challenge of penicillin had a positive skin test upon retesting. We believe that the described penicillin allergy testing procedure in children and adolescents with a history of allergy to penicillin or certain analogs is a safe, highly predictive, nonsensitizing office procedure in the hands of physicians experienced with skin testing. It should be considered for all such individuals labeled as allergic to penicillin when they are well and not in immediate need of penicillin.