Antituberculosis drug–induced hypersensitivity: clinical characteristics and risk factors

Background: Antituberculosis drugs can cause hypersensitivity reactions that interrupt treatment and increase morbidity. Early identification and management are essential to prevent complications and drug resistance.Objective: To evaluate the clinical characteristics, risk factors, and outcomes of antituberculosis drug–induced hypersensitivity reactions over a 10-year period in a tertiary referral center. Methods: We retrospectively analyzed 449 patients hospitalized for antituberculosis drug–induced hypersensitivity between 2015 and 2024. A control group of 478 tuberculosis patients without hypersensitivity was included. Demographic features, comorbidities, hypersensitivity types, causative drugs, and treatment outcomes were compared. Results: The prevalence of hypersensitivity was 12.1%. Female gender, older age, Turkish nationality, and history of other drug allergies were significant risk factors. Type 1 reactions (77.7%) were more common and associated with shorter treatment interruption and higher cure rates. Pyrazinamide was the most frequently implicated drug. Desensitization was successful in the majority of patients. Conclusion: This large cohort study highlights key risk factors and clinical outcomes in tuberculosis drug hypersensitivity. Close monitoring of high-risk patients in the early treatment phase may reduce delays and improve outcomes.