Clarithromycin hypersensitivity in children: Is there a link with β-lactam hypersensitivity?

Area of Science:

• Pediatric Allergy and Immunology
• Pharmacovigilance
• Antibiotic Hypersensitivity

Background:

• Clarithromycin is a common alternative for children with suspected beta-lactam antibiotic allergy.
• Non-beta-lactam antibiotic allergies are often attributed to clarithromycin in pediatric populations.
• Accurate diagnosis of drug hypersensitivity is critical, as skin tests have variable diagnostic value.

Purpose of the Study:

• To determine the actual rate of clarithromycin hypersensitivity in children with suspected allergy.
• To investigate the relationship between clarithromycin hypersensitivity and prior beta-lactam allergy.
• To evaluate the diagnostic utility of skin tests for clarithromycin hypersensitivity.

Main Methods:

• Retrospective analysis of medical records for 160 children referred for suspected clarithromycin hypersensitivity.
• Inclusion of clinical history, skin tests, and oral provocation tests in the allergy workup.
• Statistical analysis to identify risk factors for confirmed hypersensitivity.

Main Results:

• Confirmed clarithromycin hypersensitivity was low at 5.6% (9/160) via oral provocation tests.
• Clarithromycin skin tests showed high positivity (32.6%) but low sensitivity, with 73.9% specificity.
• Prior beta-lactam hypersensitivity and sequential clarithromycin use after amoxicillin-clavulanic acid rash were significant risk factors.

Conclusions:

• The prevalence of confirmed clarithromycin hypersensitivity among children with suspected allergy is low.
• Oral provocation testing is the definitive diagnostic method for clarithromycin hypersensitivity.
• Beta-lactam allergy, particularly in specific sequential usage contexts, is a risk factor for clarithromycin hypersensitivity.