A SURVEY OF rpoB AND katG GENE MUTATIONS OF Mycobacterium tubercolosis ON PATIENTS WITH RIFAMPICIN RESISTANT PULMONARY TUBERCULOSIS IN VINH LONG LUNG HOSPITAL

Introduction: Tuberculosis (TB) is currently a serious social disease due to its rapid spread within communities according to reports from the World Health Organization. Despite significant achievements in TB control in recent years, it remains one of the major public health issues globally. Research Objective: Determine the rate and types of rpoB and katG gene mutations in patients with pulmonary tuberculosis resistant to rifampicin and isoniazid in Vinh Long Lung Hospital. Research Subjects and Methods: A cross-sectional descriptive study is conducted on 412 eligible samples using Real-time PCR machines (Roto-Gene Q, Bio-Rad CFX96). Results: A study of 19 rifampicin-resistant samples reveals that 42.1% are multidrug-resistant (R+H), 31.5% are rifampicin-resistant only, and 5.2% are INH-resistant only. Mutations in the rpoB gene are detected in 73.7% of samples, primarily at codon 531 (S450L, 50%) and 526 (H445L, 21.4%). Mutations in the katG gene are found in 47.4% of INH-resistant samples with 88.9% at S315T position. The mutation rates for rpoB and katG genes are higher in new tuberculosis cases, but the differences are not statistically significant. Conclusions: The mutation rates of the rpoB and katG genes in rifampicin-resistant tuberculosis are 73.7% and 42.1%, respectively. rpoB mutations are concentrated at codons 526 and 531, while katG mutations predominantly occur at S315T. These findings provide a basis for understanding drug resistance mechanisms and support improvements in treatment strategies.