Potential risk factors in MDR-TB patients with acquired resistance to who group a second-line drugs

Abstract

Background. Acquired Resistance to WHO Group A second-line drugs like bedaquiline and linezolid is a new threat to treatment outcomes in patients with multi-drug resistant tuberculosis (MDR-TB). To improve treatment success and prevent resistance amplification, identifying patient-level risk factors is critical. Objective(s). To assess the clinical and sociodemographic factors associated with MDR-TB patients with treatment failure and acquired resistance to WHO Group A second-line drugs under the National TB program-PNRT. Materials and methods. This retrospective cohort study included patients with microbiologically confirmed pulmonary MDR-TB treated under PNRT between 01.01.2021 and 31.12.2022. Patients were grouped by presence/absence of acquired drug resistance. Variables analysed included age, sex, HIV status, education, residence, prior-TB and radiographic findings. Results. There were no significant differences between groups in age, sex, HIV co-infection, urban residence, homelessness, or cavitary lesions on chest imaging. However, all patients with acquired resistance had a history of prior TB infection (19/19; 100%), compared to those without infection 20/29 (69.0%) (p=0.007). Lower secondary education was more prevalent among those with acquired resistance (68.4%) compared to those without (27.6%) (p=0.008). Conclusion(s). Previous episodes of TB and lower secondary education were more frequent in patients with acquired resistance to WHO group A second-line drugs. To reduce resistance in high risk MDR-TB populations, enhanced adherence strategies and targeted education efforts are needed.