Molecular typing and drug resistance of 34 clinical isolates of Mycobacterium kansasii in He'nan Province
Objective To understand the typing and drug sensitivity results of M. kansasii strains in He'nan Province,and to provide basic data for the prevention and treatment of M. kansasii infections. Methods Positive cultures preliminarily identified as nontuberculous mycobacteria from designated tuberculosis medical institutions across He'nan Province from 2019 to 2022 were collected for strain identification. The minimum inhibitory concentration (MIC) of 11 drugs of 34 clinical isolates of M. kansasii was determined by the microdilution method. PCR-restriction enzyme pattern analysis was used for typing. Results As a result,34 clinical isolates of M. kansasii were totally sensitive to three drugs:amikacin,linezolid,and rifampicin. The MIC50 and MIC90 of amikacin,linezolid,and rifampicin were 2 mg/L and 4 mg/L,1 mg/L and 1 mg/L,and 0.25 mg/L and 0.25 mg/L,respectively. The resistance rates to clarithromycin,rifampicin,minocycline,moxifloxacin,and trimethoprim/sulfamethoxazole were 2.94％,8.82％,2.94％,5.88％,and 11.76％,respectively. The MIC50 and MIC90 of clarithromycin,rifampicin,minocycline,moxifloxacin,and trimethoprim/sulfamethoxazole were 1 mg/L and 1 mg/L,0.5 mg/L and 1 mg/L,1 mg/L and 2 mg/L,0.25 mg/L and 0.25 mg/L,as well as 0.25/4.75 mg/L and 8/152 mg/L,respectively. The clinical isolates of M. kansasii showed relatively high resistance rates to doxycycline,ethambutol,and ciprofloxacin,with resistance rates of 94.12％,50.00％,and 44.12％,respectively. Thirty-four strains of M. kansasii showed varying degrees of resistance to 11 antibiotics,while there were a total of 25 strains (73.53％) resistant to more than two drugs and a total of 4 strains (11.76％) resistant to more than four drugs. According to PCR-restriction enzyme pattern analysis,34 strains of M. kansasii belong to subtype Ⅰ. Conclusions Clarithromycin,rifampicin,amikacin,linezolid,minocycline,moxifloxacin,rifampicin,and trimethoprim/sulfamethoxazole have good in vitro antibacterial activity against clinical strains of M. kansasii isolated from He'nan Province mainly consisted of subtype Ⅰ.
万方数据
维普
