Diabetes and multidrug-resistance gene mutation: tuberculosis in Zunyi, Southwest China

BACKGROUND The aim of this study was to clarify the characteristics of gene mutation related to multidrug-resistance (MDR) of tuberculosis (TB) and diabetes in Zunyi. METHODS A total 763 patients with TB were screened for TB-DNA, TB-RNA, and acid-fast staining (all were positive). They were divided into the tuberculosis (TB) group and the diabetes mellitus-tuberculosis (DM-TB) group. We compared and analyzed the MDR gene rpoB, KatG, and inhA characteristics of gene mutations in the two groups by polymerase chain reaction (PCR)-reverse dot hybridization, and collected relevant clinical data to explore its correlation with the occurrence of multidrug resistance. RESULTS Multidrug resistance occurred in 32 of the 525 patients in the TB group, and extensive drug resistance occurred in 15 of the 207 patients in the DM-TB group. In the DM-TB group, the mutation rates of ropBS531L and ropB531 (both 53.33%) were lower than those of the TB group (both 59.38%) in rifampicin resistance mutations. Most of the mutations were at the KatG315N site, conferring isoniazid resistance. CONCLUSIONS The mutation sites of multidrug-resistant patients in Zunyi are mainly ropB531 and ropBS531L mutations, which are prone to co-occurrence; patients with MDR-TB alone are prone to mutations at the KatG315N site, while patients with diabetes and MDR-TB are more likely to have inhA15M site mutations.