Characterization of Drug Resistance Patterns, Mutation Profiles and Prevalence of <i>Mycobacterium tuberculosis</i> in Shaoxing

Objective This study aimed to analyze drug resistance patterns, mutation profiles in Mycobacterium tuberculosis isolates and clinical characteristics of tuberculosis patients in Shaoxing, Zhejiang, China. Methods Clinical specimens and data from tuberculosis patients admitted in 2024 were collected. Cultures were established using the MGIT liquid culture system, and drug susceptibility to twelve anti-tuberculosis agents (four first-line and eight second-line) was assessed by the microbroth dilution method. Mutations in the rpoB gene, katG gene, and inhA promoter were identified using a DNA microarray chip assay. Results Among 268 Mycobacterium tuberculosis isolates, 62 (23.1%) exhibited resistance to at least one anti-tuberculosis drug. These comprised 21 (7.8%) mono-resistant, 25 (9.3%) poly-resistant, and 16 (6.0%) multidrug-resistant strains, including 3 (1.1%) classified as pre-extensively drug-resistant and 1 (0.4%) as extensively drug-resistant. Among rifampicin-resistant isolates, mutations at codons 531 (47.4%) and 526 (21.1%) of the rpoB gene were most frequent, while the katG Ser315Thr substitution was detected in 44.8% of isoniazid-resistant strains. Compared with primary cases, re-treated patients were more frequently over 50 years of age, exhibited a higher prevalence of pulmonary cavities, and showed significantly elevated rates of drug resistance (P Conclusion Our findings indicate that although the overall prevalence of drug-resistant tuberculosis in Shaoxing remains low, the resistance patterns are heterogeneous. These results underscore the need for comprehensive drug susceptibility and genetic testing to guide effective treatment strategies.