Traditional skin tests used to predict allergies to antibiotics are useless say Montreal researchers

http://www.eurekalert.org/pub_releases/2016-04/muhc-tst040716.php

Public Release: 7-Apr-2016
Traditional skin tests used to predict allergies to antibiotics are useless say Montreal researchers
McGill University Health Centre

Skin tests traditionally used to predict allergies to amoxicillin, one of the most commonly prescribed antibiotics in children, are ineffective according to a new study led by a team at the Research Institute of the McGill University Health Centre (RI-MUHC) in Montreal. The findings, published in the journal JAMA Pediatrics this week, determined that oral provocation or challenge test, with appropriate follow up, was a more efficient and safer screening method for diagnosing non-life threatening reactions to amoxicillin in children.

"Our study suggests that skin tests are essentially useless as diagnostic tests, and that we should go directly to the graded provocation test that is highly sensitive and specific," says study's lead author Dr. Moshe Ben-Shoshan, who is an allergist at the Montreal Children's Hospital at the MUHC (MCH-MUHC) and an assistant professor of Pediatrics at McGill University. "This is a game changer in the way physicians assess amoxicillin allergy in children given the fact that skin tests are still the recommended screening method in hospitals."

Provocation or challenge (PC) tests are performed with the suspected allergen (for example pollen, food or drug) which involves gradual introduction of the allergen to the patient. Challenge tests are performed in a hospital or clinic, where any serious reactions can be safely managed.

Up to 10 per cent of children develop rashes while on antibiotics. "The majority are diagnosed without further evaluation as allergic to the implicated antibiotic," explains Dr. Ben-Shoshan who is also a researcher from the Infectious Diseases and Immunity in Global Health Program of the RI-MUHC. "Most of the patients continue to avoid the suspect antibiotic in favor of alternatives which may be less effective, more toxic, and more expensive."

•••••