Geno-typing and drug resistance gene analysis of Salmonella in Chinese PLA General Hospital from 2015 to 2017

Abstract

Objective To understand the prevalence of Salmonella and the characteristics of drug resistance genes in General Hospital of People′s Liberation Army, and to provide evidence for the prevention and treatment of Salmonella infection. Methods A retrospective study was conducted to collect 78 clinical isolates of Salmonella from 2015 to 2017. The age of the patients was 49±21 years old. The infected patients were mainly young and middle-aged. The clinical samples mainly came from feces and venous blood, accounting for 44.87% (35/78) and 33.33% (26/78), respectively. After serotype identification, drug sensitivity test and whole genome sequencing, multilocus sequence typing and drug resistance genotyping were performed. Cluster of Cefotaxime or Ciprofloxacin resistant Salmonella was analyzed. Results Salmonella group D (53.85%) and Salmonella group C (21.79%) were dominant Salmonella serotype. ST11 was mainly ST type. Drug sensitivity test showed that the multidrug resistance rate of Salmonella was 64.11% (50/78). The sensitivity to all antimicrobial agents′ rate was 25.64 (20/78). The resistance rate of Salmonella to nalidixic acid was 65.38% (51/78). The most common drug resistance gene of Salmonella was extended-spectrum β-lactam drug resistance gene, accounting for 78.21% (61/78). Conclusions The ST-type and carrying resistance genes of Salmonella in this hospital were diverse. Most pathogens were multi-drug resistant to antimicrobial agents. Molecular typing and drug resistance gene analysis of Salmonella and construction of resistant strains to determine the inheritance of Salmonella relationships have a certain clinical significance. Key words: Salmonella; Drug resistance, bacterial; Multilocus sequence typing