Molecular Characterization and Antibiograms of Nontuberculous Mycobacterium Infections in Kashgar, China

To investigate the prevalent characteristic of nontuberculous mycobacteria (NTM) isolates in Kashgar. A total of 52 NTM culture-positive isolates were collected in 2020 from Kashgar, China. All strains were confirmed to be NTM species by whole genome sequencing (WGS). Drug susceptibility testing was performed using Sensititre SLOMYCO plates. Of the 52 NTM isolates, 88.46% (46/52) were rapidly growing mycobacteria (RGM). The predominant NTM species were Mycolicibacterium. sp (23.07%, 12/52) and M. elephantis (15.38%, 8/52), followed by Mycobacteroides chelonae (9.61%, 5/52). At least, two suspected new species were identified. Two core virulence genes were identified in more than 95% of the isolates. Antimicrobial susceptibility testing revealed high resistance among RGM isolates to imipenem (73.91%), while remained sensitive to amikacin and ciprofloxacin. All slowly growing mycobacteria isolates exhibited the highest resistance rate against doxycycline (83.3%, 5/6), but most strains were sensitive to clarithromycin, rifabutin, amikacin, ciprofloxacin, moxifloxacin, rifampin, and trimethoprim-sulfamethoxazole. The prevalence of NTM isolates in Kashgar presents a very specific features and some rarely reported species constitute big proportions. Amikacin and moxifloxacin may represent effective therapeutic options for NTM infections in Kashgar.