Reproducibility of delayed-type reactions to betalactams

Abstract

Simple blind oral challenge with implicated drug followed by home treatment is required for a conclusive diagnosis of allergy in patients with delayed reactions to betalactams.

Drug hypersensitivity in children: report from the pediatric task force of theEAACIDrug Allergy Interest Group

“…Various intervals for incremental doses have been described, ranging from 20 min to 1 week . For example, an interval of 30 min to 2 h is generally appropriate for immediate reactions, whereas for nonimmediate exanthemas, longer intervals may be considered (weak) .…”

“…The aim of the DPT is to confirm or exclude a reaction or to find safe alternative treatments, in case of confirmed DH to the culprit drug. Whereas the risk for future reactions can be further reduced by giving a full daily dose, or even 3, 5, and 7‐day administration, the members of the Task Force panel believe that exposing on full single therapeutical dose is sufficient for most cases (weak) .…”

“…However, these data need to be confirmed in different populations in large prospective studies. An open oral DTP seems to be sufficient in most pediatric cases, and only a few studies refer to blinded placebo‐controlled tests (weak) .…”

“…The investigation of suspected reactions using the available methods allows the exclusion of DH in the vast majority of the suspected cases .…”

Drug provocation tests in hypersensitivity drug reactions

“…With regard to delayed urticaria and maculopapular exanthema from aminopenicillin, the value of skin testing in these cases is very low [24][25][26], as 4-9% of cases confirmed by DPT have a delayed intradermal skin test (IDT) or patch test positivity [24,25]. Moreover, in most instances, exanthema appearing in the course of drug treatment is due to other causes [27,28].…”