Comprehensive allergy work-up is mandatory in cystic fibrosis patients who report a history suggestive of drug allergy to beta-lactam antibiotics

The study, part of the Drug Allergy and Hypersensitivity (DAHD) cohort, was performed in the regional cystic fibrosis center of Montpellier, France. After identifying patients with a clinical history suggestive of drug allergy to ？-lactams, a complete drug allergy work-up, was carried out according to the EAACI recommendations.Among the 171 patients involved, 23 reported clinical manifestations potentially compatible with a drug allergy to ？-lactams. After performing the complete drug-allergy work-up, 7 were considered as drug hypersensitive (3 had positive skin tests, 1 a positive provocation test, 3 declined the tests). Excluding the latter 3 patients with incomplete drug allergy work-up, the rate of proven drug allergy was 2.3%.Drug allergy to ？-lactams in cystic fibrosis patients is of importance. A full drug allergy work-up is mandatory in case of suspicion, because ？-lactam responsibility is often ruled out.Cystic fibrosis (CF) is a chronic disease for which chronic therapies are required to slow the progression of disease [1]. Patients with CF suffer daily symptoms, frequent exacerbations of pulmonary infection, and an early demise [2]. Chronic airway inflammation and infection are indeed the greatest causes of mortality and morbidity in patients with CF, the resulting lung damages being the main cause of death [1,3,4]. Antibiotics are typically used for early, intermittent infection, with the goal being to eradicate the pathogen [2]. Antibacterial therapies are instituted empirically and are individualized based on both patient’s factors (severity of exacerbation, frequency of exacerbation, recent courses of anti-infectives) and pathogen factors (previously isolated pathogens and in vitro predicted antibiotic susceptibilities) [5].The French registry on CF reported that, in 2007, more than 75% of the 4806 patients who underwent a common cytobacteriologic examination of the sputum (93.5% of the CF patients treated in France) were infected by a non-commensal b