Prevalence of rifampicin-resistant Mycobacterium tuberculosis by CBNAAT in a tertiary care hospital of West Bengal, India

Abstract

Background: Tuberculosis (TB) remains one of the commonest infectious diseases in India, where control is difficult due to the emergence of multi-drug-resistant TB (MDR-TB). The rifampicin resistance (RR) is an important surrogate marker of MDR-TB. Aims and Objectives: The aim of this article is to determine the prevalence of RR-TB among all symptomatic presumptive TB patients by cartridge-based nucleic acid amplification test (CBNAAT) in our institution. Materials and Methods: A retrospective cross-sectional study was conducted from January 2018 to December 2020 in the Directly Observed Treatment (DOT) center of a tertiary care hospital. All presumptive cases of pulmonary TB patients coming to the DOT center were subjected to CBNAAT by GeneXpert Mycobacterium tuberculosis rifampicin (MTB/RIF) (Cepheid). Data were collected from a data-extraction sheet from registration books and analyzed using SPSS version 20. Fisher’s exact test was applied to examine the association between categorical variables and P-value less than 0.05 was considered significant. Results: A total of 6171 presumptive TB patients were included in the study. The overall prevalence of TB was 1590 (25.77%) in all age groups. The prevalence of RR-TB among all confirmed TB cases was 10.75% (171/1590) with the majority being males (130 cases). The prevalence of RR cases among new and previously treated was 3.1% and 36.34%, respectively, which were statistically significant (P < 0.05). Conclusion: We found that RR-TB is still much prevalent in our area, and it was significantly higher in previously treated cases. The CBNAAT is a good molecular assay method for rapid detection of TB and also for the detection of RR-TB.