Suspected Reaction With Cephalosporin May Be a Predictive Factor for β-Lactam Allergy in Children

Luke A. Wall

doi:10.1542/peds.2019-2461X

I Eser Simsek, M Tuba Cogurlu, M Aydogan. Int Arch Allergy Immunol. 2019;178(3):248–254

Purpose of the Study:

To determine the frequency and risk factors of confirmed allergy in patients who report β-lactam allergy and evaluate cross-reactivity between β-lactams in children with confirmed allergy.

Study Population:

The population included 67 children evaluated at an academic allergy and immunology practice in Turkey from 2012 to 2017.

Methods:

All patients referred to an outpatient clinic with history of immediate reaction to β-lactam antibiotics were included. Patients completed a questionnaire and underwent workup on the basis of the European Network for Drug Allergy guidelines. Serum-specific immunoglobulin E to penicilloyl V, penicilloyl G, amoxicilloyl, and ampicilloyl were measured by UniCAP in all patients. Patients with undetectable serum results underwent skin prick tests (SPTs). Intradermal testing was performed if the SPT result was negative. A drug provocation test with suspected β-lactam was performed in patients with negative workup.

Results:

β-lactam allergy was confirmed in 14.9% of patients who reported a history of allergy. All of the allergic patients had negative results on SPT and serology. Four patients with negative intradermal results had a reaction (urticaria) with the drug provocation test. Age, sex, time interval since reaction, atopy, reaction type, parental history of drug allergy, and multiple drug allergy history were not significantly different between allergic and tolerant patients. The rate of confirmed diagnosis was higher for the group that reported cephalosporin allergy compared with report of penicillin allergy (P = .03). Three patients with allergy to penicillin tolerated cefuroxime. Four patients with selective allergy to ceftriaxone tolerated cephalosporins with dissimilar side chains.

Conclusions:

Appropriate evaluation of suspected drug allergy will lead to accurate diagnoses and reduce the use of less-effective yet more-expensive alternative antibiotics.

Reviewer Comments:

This study supports a large body of literature demonstrating that most patients who report a β-lactam allergy tolerate the drug. Neither serum immunoglobulin E testing nor SPT alone are sufficient to evaluate β-lactam allergy. Even intradermal testing may miss some truly allergic patients. The gold standard, drug provocation challenge, is required to confirm a diagnosis of allergy. The clinical history and available diagnostic results must be weighed to determine if drug provocation challenge is appropriate because reactions in allergic individuals can be potentially life-threatening.