Abstract: Objective To understand the current status of drug resistance to commonly used anti-tuberculosis drugs in pulmonary tuberculosis patients in Sichuan Province for reference for following precise prevention and control of drug-resistant tuberculosis. Methods Mycobacterium culture-positive patients enrolled in the Tuberculosis Drug Resistance Surveillance Program of Sichuan Province from January to December 2024 were selected as study subjects. The types, categories, and spectra of drug resistance to six common anti-tuberculosis drugs, including isoniazid (INH), rifampicin (RFP), levofloxacin (LFX), moxifloxacin (MFX), bedaquiline (BDQ), and linezolid (LZD), were sorted out, and the factors for drug-resistant tuberculosis were analyzed by multivariate logistic regression model. Results Among 1 388 patients, the overall drug resistance rate was 20.97% (291/1 388). The drug resistance rate in newly treated patients was 19.87% (253/1 273), which was significantly lower than that of retreated patients (33.04%, 38/115). The drug resistance rates to six common anti-tuberculosis drugs, ranking from the highest to the lowest, were as follows: INH (11.60%, 161/1 388), LFX (9.37%, 130/1 388), MFX (9.08%, 126/1 388), RFP (5.48%, 76/1 388), BDQ (2.23%, 31/1 388), and LZD (1.51%, 21/1 388). The most prevalent drug resistance profile was LFX+MFX, with a resistance rate being 6.05% (84/1 388). Multivariate logistic regression analysis showed that the patients with retreatment (OR=1.880, 95%CI: 1.228-2.837) or diagnosis delay ≥14 days (OR=1.423, 95%CI: 1.036-1.938) had a significantly higher risk to develop drug resistance, whereas those with negative smears (OR=0.718, 95%CI: 0.549-0.936) had a lower risk of developing drug resistance. Conclusion At present, the drug resistance to INH and fluoroquinolones (FQs) among pulmonary tuberculosis patients in Sichuan Province was relatively serious, and the risks of developing drug resistance is higher in patients with retreatment and delayed diagnosis. The findings suggest that it is imperative to strengthen the standardized management of retreated pulmonary tuberculosis patients, improve the timeliness and accuracy of clinical diagnosis and treatment, so as to effectively control the occurrence of drug-resistant tuberculosis in Sichuan Province. 

Key words: Drug-resistant pulmonary tuberculosis, Drug sensitivity test, Influencing factors, Sichuan Province