Hypersensitivity to paracetamol in Asian children with early onset of nonsteroidal anti-inflammatory drug allergy.

Background: The published incidence of paracetamol cross-reactivity in adults and adolescents with nonsteroidal anti-inflammatory drug (NSAID) reactions is low and all data on such reactions in young children is sparse. The study aim was to characterize the clinical presentation and cross-reactivity with paracetamol in patients with a reported onset of NSAID hypersensitivity before 6 years of age.

Methods: A retrospective case review was done of patients with cross-reactive hypersensitivity reactions to antipyretic/analgesic medications from the pediatric allergy clinic of the Kendang Kerbau Hospital, Singapore. Included patients reported the onset of such reactions before 6 years of age. Hypersensitivity was established through a detailed history of recurrent reactions to NSAIDs or an oral provocation test.

Results: Eighteen patients fulfilled the diagnostic criteria within the study period. Eighty-three percent had cross-reactive reactions with paracetamol. When compared to the group of children with later onset of NSAID hypersensitivity, children with onset before 6 years of age had a significantly increased likelihood of reacting to paracetamol (odds ratio 9.6, 95% confidence interval 1.6-58.0, p < 0.05).

Conclusion: Paracetamol seems to be a major eliciting drug in this group of children.