Skin tests are important in children with β‐lactam hypersensitivity, but may be reduced in number

Abstract

Background There is no perfect agreement on how to perform an allergy workup in suspected beta‐lactam (BL)–allergic children, since skin test (ST)–induced pain is often a limitation. The aim of the study was to assess the possibility of reducing the number of ST in children when performing a complete allergy workup for BL hypersensitivity reactions. Methods A retrospective analysis of all patients referring to the Allergy Unit of the University Hospital of Montpellier (France) with positive responses in immediateand non–immediate‐reading ST to a BL over a 16‐year period was performed, to determine the positive predictive value (PPV) of ST. All pediatric patients with a suspected BL hypersensitivity were skin‐tested with the suspected drug only, during the following 54 months. Results A total of 319 patients reporting 328 BL reactions were included in the retrospective study. The PPV of ST for the reported drug was of 99.4%. Based on the results, the number of patients to include in the prospective study was estimated to be 101. In the prospective study, 229 children were included. We diagnosed a BL hypersensitivity in 12 children (5.2%): Diagnosis was reached in 6 (50.0%) through ST (delayed reading for all) and in 6 through drug provocation test (DPT). Conclusion ST with BL should therefore be performed as a screening test, before DPT, and testing only the suspected drug may be sufficient when dealing with children.

Recent developments and highlights in drug hypersensitivity

“…84 However, in a retrospective study, STs have demonstrated a PPV of 99.4%, indicating their usefulness, before DPT. 85 Large multicentre studies, to evaluate the real diagnostic predictive values of ST, are needed. 86 In the case of NIR, due to the potential risk of triggering a severe reaction, the diagnostic procedure starts with a patch test and if negative, IDTs, although recent studies suggest the performance of IDTs with no need of a previous patch testing.…”

Practical guide for evaluation and management of beta-lactam allergy: position statement from the Canadian Society of Allergy and Clinical Immunology

“…In one retrospective review, patients with a nebulous history of penicillin allergy had rates of skin sensitization identical to that of patients without a penicillin allergy history (1.7%) [34]. Although a positive penicillin skin test result is often considered the reference standard for penicillin allergy, some patients may be sensitized (i.e., positive skin test result) but not clinically allergic, as shown by a negative oral penicillin challenge [35,36]. Standardized skin tests for cephalosporins are not available, although non-irritating concentrations for skin-testing have been published [37].…”

Advances and novel developments in drug hypersensitivity diagnosis

“…56 Finally, controversies exist about the reported safety and cost-effectiveness of direct DPT without previous STs for penicillin allergy delabeling in low-risk patients, [57][58][59][60] while others recommend to perform it with the culprit in all children with suspected BL hypersensitivity. 61 Importantly, the last position paper from the EAACI, in patients with BL allergy, recommends this procedure in children with mild maculopapular exanthema, although it is not recommended in adults experiencing low-risk NI-DHRs other than palmar exfoliative exanthema. 3 Further studies are necessary to provide data regarding the standardization of protocols for DPT, especially of those regarding NI-DHRs, for which there is currently no consensus.…”