Higher Prevalence of Multi-Antimicrobial Resistant spp. Strains Isolated at a Tertiary Teaching Hospital in China.

Purpose: The study investigates the molecular epidemiology of multi-drug resistant (MDR) spp. isolates and the clinical characteristics of the patients.

Materials And Methods: spp. clinical strains were identified through MALDI-TOF MS and VITEK-2 anaerobes and corynebacterium (ANC) cards. A broth microdilution method was employed to detect the antimicrobial sensitivities of spp. isolates. PCR was used to detect the resistance genes, including , as well as the upstream insertion sequence (IS) element of the gene. The effects of broad-spectrum efflux pump inhibitors (EPIs) on the minimal inhibitory concentration (MICs) of cefoxitin, moxifloxacin, and imipenem for MDR spp. were investigated.

Results: The total resistance rates of 115 spp. isolates to cefoxitin, moxifloxacin, clindamycin, metronidazole, imipenem and meropenem were 4.3%, 16.5%, 80.0%, 5.2%, 13.9% and 13.9%, respectively. The positive rates of carbapenem resistance gene were 38.9% and 8.6% for and non- isolates, respectively. The isolation rate of MDR isolates reached up to 18.26% (21/115), and the isolation rate among the gastrointestinal cancer patients was significantly higher when compared to the non-gastrointestinal cancer patients (52.38%/26.08%, = 0.006). Furthermore, MDR isolates were more likely to be isolated from the patients exposed to cephalosporins 3 months before spp. isolation (76.19%/31.52%, = 0.000).

Conclusion: The overall resistance rates of spp. isolates against multiple antimicrobials were at a high level, especially for . The gene carrying rate among isolates was as high as 38.9%, and its mediated carbapenem resistance was the major resistance mechanism for . The findings of this study imply that the real resistance tendency of spp. may be underestimated and need to be given more attention.