Pyrazinamide Resistance among Multi Drug Resistant Tuberculosis Patients in Karnataka: Cross Sectional Study from a Referral Centre

Abstract

This study aimed to investigate the rate of occurrence of pyrazinamide (PZA) resistance among patients with MDR-TB from the clinical specimens submitted to a referral centre in Bengaluru, Karnataka. PZA has been used for almost 50 years as first line drug for short course chemotherapy against MTB and its inclusion has significantly shortened the treatment duration to 6 months. However, resistance to PZA is associated with poor treatment outcomes and its drug susceptibility testing (DST) is not routinely performed in public health laboratories in India due to technical difficulties. This study followed a structured approach to investigate PZA resistance among MDRTB patients in Karnataka. Relevant demographic and clinical information was collected from Laboratory registers. The specimens yielding the growth of Mycobacterium tuberculosis were subjected to DST for PZA using validated techniques and the rate of PZA resistance was determined. Our results showed 4% of PZA resistance among MDRTB specimens. These results can contribute to the understanding of local epidemiology of drug resistant TB and update public health strategies for TB control in a particular geographical region. The findings may highlight the need for routine DST for PZA in public health laboratories in India and further research to better understand the associated factors with PZA resistance. This study also emphasizes the importance of continued surveillance of drug resistance patterns to guide evidence-based interventions for TB control and management.