Objective: The aim of the study was to investigate true β-lactam allergy at a public pediatric hospital. Material and Methods: Children and adolescents with allergy symptoms were referred to the Allergy and Immunology Service, Hospital Infantil Albert Sabin, Fortaleza, Brazil. During the allergist interviews, β-lactam drug allergy was suspected in 24 patients. Results: Urticaria, angioedema, erythematous macules and papules were the clinical manifestations most frequently reported in 23 patients with immediate reaction. The drugs implicated were amoxicillin (58.3%), penicillin (20.8%), ceftriaxone (12.5%) and ampicillin (8.4%). The majority of the patients showed negative results for ampicillin, penicillin and ceftriaxone in skin testing and also negative results in oral provocation testing (OPT) to amoxicillin. One patient with clinical history of ceftriaxone allergy showed positive prick test to the drug and negative OPT to amoxicillin. Conclusion: b-lactam drugs are a very useful choice for treatment of bacterial infections in children. In this way, it is reasonable that hypothesis of allergy to those drugs be investigated. For this reason, during consultation, it is necessary that the allergist questions about drug allergy, apart from the original complaint (if it is not directly related to drug allergy). Upon suggestive history, the hypothesis of drug allergy should be ruled out by doing a careful laboratorial and clinical investigation. In order to rationalize the operating and economical costs related to skin testing and OPT, we suggest grouping a number of patients for whom the tests will be performed during a half-day period two to three times a year.
Key words: Allergy, Beta-lactamic, Hypersensitivity, Pediatric, Public hospital.