Skin tests and in vitro allergy tests have a poor diagnostic value for benign skin rashes due to β‐lactams in children

Oral challenge without skin tests in children with non‐severe beta‐lactam hypersensitivity: Time to change the paradigm?

“…In benign non‐immediate BLH (without any danger sign), the most common clinical scenario in childhood, it has been recommended to perform intradermal tests (delayed‐reading) and, if negative, an oral provocation test (OPT) to the index antibiotic. Of note, lymphocyte transformation tests and patch tests have been shown to be not efficient for the diagnosis of benign non‐immediate reactions to beta‐lactams in children . Considering that most children (more than 90%) are not confirmed as allergic, this algorithm is heavily resource‐intensive and time‐consuming or could even lead to a number of wrong diagnoses of drug hypersensitivity due to uncertain predictive values of skin tests.…”

“…To evaluate the real diagnostic value of skin tests, they performed a follow‐up study to include more patients with a positive OPT. Their results showed that the sensitivity of intradermal test was 50% and the specificity 91.5% . Given the low pretest probability (prevalence of true BLH below 10%), positive predictive values of skin tests are even weaker than their sensitivity, resulting in many inaccurate BLH diagnoses.…”

How antibiotic allergy labels may be harming our most vulnerable patients

“…The deleterious effects of a β‐lactam allergy were also demonstrated in a prospective study of 507 inpatients with infectious diseases in Canada, where multivariate analysis identified that β‐lactam allergy was associated with an increased risk of adverse events (adjusted OR, 3.1; 95% CI, 1.28–7.89) and a composite endpoint of readmission, Clostridium difficile infection, drug reaction or acute kidney injury (adjusted OR, 3.18; 95% CI, 1.28–7.89) 5 . These impacts are concerning given that almost 20% of antibiotic allergy labels arise from drug side effects, 6 and most childhood antibiotic allergy labels likely reflect a viral aetiology rather than true immune‐mediated antibiotic hypersensitivity 7 . Caubet and colleagues 7 detected respiratory viruses by polymerase chain reaction of throat swab samples or serological testing in 66% of oral challenge‐negative children at the time of reported allergy, while Vezir and colleagues 8 found that over 96% of children with a non‐immediate allergy did not have their allergy reproduced on antibiotic re‐challenge.…”

“…These impacts are concerning given that almost 20% of antibiotic allergy labels arise from drug side effects, 6 and most childhood antibiotic allergy labels likely reflect a viral aetiology rather than true immune‐mediated antibiotic hypersensitivity 7 . Caubet and colleagues 7 detected respiratory viruses by polymerase chain reaction of throat swab samples or serological testing in 66% of oral challenge‐negative children at the time of reported allergy, while Vezir and colleagues 8 found that over 96% of children with a non‐immediate allergy did not have their allergy reproduced on antibiotic re‐challenge. In a seminal article, Bourke and colleagues 9 found that 90% of all penicillin allergy labels can be removed by formal penicillin skin testing and subsequent oral provocation.…”

Lack of uniformity in the investigation and management of suspected β‐lactam allergy in children

“…Studies have shown SPT to have limited accuracy, and reactions on subsequent DPC have also occurred in patients who have had negative IDT . DPC without previous SPT are well tolerated in children , and studies have shown high negative predictive values (94–98%) from challenges . However, DPC are not without risk as they potentially expose a child to a risk of anaphylaxis and are logistically demanding although the incidence of severe reactions is low (1/100,000) .…”