Distribution of M. tuberculosis infection and analysis of rifampicin and isoniazid resistance as determined in the region by high-resolution melting

Abstract Background: Identifying the transmission mode and resistance mechanism of M. tuberculosis is the key to prevent the transmission and drug resistance of M. tuberculosis. However, related data are still lacking in the region, and the purpose of this study was to investigate the transmission characteristics of the Mycobacterium tuberculosis complex and the resistance patterns of isoniazid and rifampicin, as well as multidrug-resistant tuberculosis(MDR-TB).Methods: We analyzed the high-resolution melting PCR results of sputum, alveolar lavage fluid and pleural fluid specimens in a total of 17,515 suspected or confirmed patients in downtown and nine counties of Luoyang City from 2019 to 2021, revealed the distribution and transmission characteristics of M. tuberculosis, and assessed the risk factors associated with rifampin and isoniazid resistance and MDR-TB.Results: Of the included study data, 82.6% were from rural areas and 96.0% were initial patients. overall, 16.8% cases diagnosed with tuberculosis(TB), with males (18.0%) having a higher positivity rate than females (14.1%). Consistent with our expectations, positive sputum smear was a positive factor for HRM positivity, with HRM positivity rates being much higher than smear-negative populations. By age, the highest rates of TB infection occurred in males aged 26-30 yearsand in females (28.1%) aged 21-25. The rates of resistance to rifampicin (20.5%), isoniazid (16.0%) and MDR detection (12.9%) in males were higher than 16.0%, 12.0% and 10.2% in females. The absolute value number of HRM positives in new patients was much higher than that of the groups with a history of tuberculosis treatment, but the HRM positive rate and tuberculosis drug resistance rate of the reteratment population were higher than those of new cases. Notably, males in new patients had higher rates of HRM positivity, isoniazid resistance(R-H), rifampicin resistance(R-R) and MDR-TB detection than females, and the difference was statistically significant (p<0.05), but in individuals who had received TB treatment, the above indicators were just opposite, which were higher in females than in males. The rate of HRM positive and the tuberculosis resistance of urban population is much higher than that of township population. In the multivariate model, previous treatment history, age younger than 51 years, urban area and male were significantly and positively associated with tuberculosis resistance after adjusting for smear results and year testing.Conclusions: Males were a high burden group of TB infection and drug resistance, and the detection of the local MTB-positive population, R-H, R-R and MDR-TB may be younger. More comprehensive resistance pattern monitoring is needed to control the spread of TB and manage local TB resistance.