Patterns of adverse drug reactions and treatment outcomes in drug-resistant tuberculosis: A retrospective study from a tertiary care hospital in Delhi

Background: Multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant TB (XDR-TB) pose significant global health challenges with high mortality risks. Adverse drug reactions (ADRs) further complicate treatment, impacting patient adherence and outcomes. In India, the DOTS strategy under the Revised National Tuberculosis Control Programme has been widely implemented, yet TB management is hindered by limited patient awareness, socioeconomic constraints, and gaps in healthcare provider training. This study assesses the incidence of ADRs and their impact on treatment outcomes at a tertiary care hospital in Delhi. Materials and Methods: A cross-sectional study was conducted using retrospective medical record reviews of MDR-TB and XDR-TB patients (aged ≥18 years) registered at a university hospital in Delhi from January 2017 to August 2021. Data on ADRs and treatment outcomes were extracted from outpatient records for analysis. Results: Of 213 enrolled patients, 183 were analyzed, with 72.6% experiencing at least one ADR. Males had a higher ADR incidence (58%) than females (42%). The most common ADRs were gastrointestinal disorders (21.8%), eye disorders (14.3%), and musculoskeletal disorders (14.3%), primarily linked to pyrazinamide, ethambutol, and ethionamide. Serious ADRs occurred in 17.4% of cases. Conclusion: Gastrointestinal disorders, particularly nausea and vomiting, emerged as the most commonly reported ADRs. These findings emphasize the importance of early identification of high-risk patients and the need for close monitoring throughout anti-TB treatment to support adherence and improve outcomes. This study adds valuable evidence to strengthen pharmacovigilance efforts and inform the optimization of MDR/XDR-TB treatment protocols within India's public healthcare system.