Beta-lactam hypersensitivity in children with cystic fibrosis: a study in a specialized pediatric center for cystic fibrosis and drug allergy.

ABSTRACT

BACKGROUND: Beta-lactam hypersensitivity (HS) is suspected in 5-12% of the children, but proven in only 10-15% of those children, based on skin and challenge tests results. In contrast, 30-60% of patients with cystic fibrosis (CF) are diagnosed allergic to beta-lactams, based mainly on the clinical history of the patients. OBJECTIVES: To confirm or rule out a suspected beta-lactam HS in CF children and to determine the prevalences of suspected and confirmed beta-lactam HS in those children. PATIENTS AND METHODS: Children with CF and suspected beta-lactam HS were explored by means of skin and challenge tests with the suspected and alternate beta-lactams. The results in CF children were compared with those reported in the literature in non- CF children. RESULTS: Eight of the 701 CF children followed in our center between 1990 and 2011 (1.14%), and 11 other children from other centers were explored for suspected beta-lactam HS. Beta-lactam HS was diagnosed in nine of these children (47.3%). Based on the results in the children followed in our center, the prevalence of beta-lactam HS was 0.71% (5/701) in CF children vs. a mean estimated prevalence of 1-1.5% in the general pediatric population. CONCLUSION: Our results contrast with those of most previous studies. Although half of the CF children with suspected beta-lactam HS were truly allergic to beta-lactams, the general prevalence of beta-lactam HS in CF children was very low. This may result from tolerance induced by frequent and/or prolonged treatments with beta-lactams.