African Journal of Parasitology Research

African Journal of Parasitology Research ISSN 2756-3391 Vol. 7 (3), pp. 001-006, March, 2020. © International Scholars Journals

Full Length Research Paper

In vitro susceptibility of some antimicrobials against bacteria enteropathogens

Xiaojuan Xin, Bei Jia*, Wenxiang Huang, Chengwei Liu and Chongzhi Li

Department of Infectious Diseases, the First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China.

Accepted 21 January, 2020

Abstract

To investigate the current resistant levels of enteric bacteria in southwestern China, broth dilution method was used to detect in vitro susceptibility of rifaximin, ciprofloxacin, gatifloxacin, azithromycin and trimethoprim/sulfamethoxazole (SMZ/TMP) against 101 enteropathogens isolated from cases of bacterial diarrhea of four teaching hospitals. For all the isolates, ciprofloxacin, gatifloxacin and SMZ/TMP had MIC₉₀s of 64, 32 and >128 mg/L, respectively, much higher than CLSI resistance cutoffs. Azithromycin also had very high MIC₉₀ value of >128 mg/L. The MIC₉₀ of rifaximin was 64 mg/L, much lower than the intestinal lumen concentration measured after administration of this agent. Diarrheagenic Escherichia coli were highly resistant to fluoroquinolones with resistant frequency of >40%. The in vitro activity of ciprofloxacin, gatifloxacin and azithromycin on Shigella spp was of concern with the MIC₉₀s of 64, 16 and 64 mg/L, respectively. The majority of Salmonella spp isolated retained susceptibility to the antimicrobials tested. Comparing with other regions or countries, resistance rates of enteropathogens were much higher in this area of China. Rifaximin is a promising treatment and chemophylaxis for nonsystemic bacteria diarrhea.

Key words: Antimicrobial, infectious diarrhea, enteropathogen, susceptibility.