Diagnostic evaluation of hypersensitivity reactions to beta-lactam antibiotics in a large population of children.

INTRODUCTION: Hypersensitivity reactions to beta-lactams (BLs) are often reported in children, with amoxicillin and, to a lesser extent, cephalosporins being the most frequent drugs involved. Although many of these children are considered to be allergic, a careful evaluation only confirms a low percentage.

OBJECTIVES: To analyse the clinical data, sensitization profile and diagnostic methods used in a large group of children with a clinical history of hypersensitivity reactions to BLs.

METHODS: The study included children aged 1-14 yr with symptoms suggestive of hypersensitivity to BLs from January 2006-December 2012. Diagnosis was confirmed from a clinical history, specific IgE determination, skin testing and, if necessary, a drug provocation test (DPT).

RESULTS: Of a total of 783 patients studied, only 62 (7.92%) were confirmed as being allergic, 9 (14.52%) with immediate and 53 (85.48%) with non-immediate reactions. In those with immediate reactions, 2 (22.22%) were diagnosed by in vitro test, 2 (22.22%) by skin testing and 5 (55.56%) by DPT; in those with non-immediate reactions, 2 (3.77%) were diagnosed by skin testing and 51 (96.23%) by DPT. In all cases, DPT was positive to the culprit drug (29 AX-CLV, 26 AX, 1 cefixime and 1 cefaclor), and the most usual symptoms were exanthema in 43 cases, urticaria in 12, urticaria-angio-oedema in 1 and erythema in 1 case.

CONCLUSION: After an allergological work-up, over 90% of the children evaluated were finally confirmed as tolerant to BLs. Most reactions were of the non-immediate type, and DPT was an essential tool for diagnosis.