Drug resistance and molecular epidemiology of Acinetobacter baumannii isolated from pediatric patients

Abstract

Objective To analyze the drug resistance and molecular epidemiological characteristics of Acinetobacter baumannii isolated from pediatric patients. Methods Acinetobacter baumannii isolated from patients hospitalized in Inner Mongolia Medical University Affiliated Hospital from January 2016 to June 2018 was collected.Vitek-2 Compact automatic microbiological identification and drug sensitivity analysis system was used to identify and test the drug sensitivity of Acinetobacter baumannii isolates, and pulse field gel electrophoresis (PFGE) and multilocus sequence analysis (MLST) were applied to the homology analysis of the strains. Results A total of 94 clinical isolates of Acinetobacter baumannii were collected, of which 42 strains were isolated from pediatric patients and 52 strains from adult patients.The drug resistance rates of pediatric isolates to Imipenem, and Meropenem and Tigecycline were 7.1%, 7.1% and 0, respectively, and the drug resistance rates of adult isolates to these 3 antibiotics were 67.3%, 54.8%, and 5.5%, respectively.The results of PFGE typing showed that 94 strains were divided into 49 genotypes (X1-X49 type), 52 adult strains were distributed in 22 genotypes, and 42 pediatric strains were distributed in 33 genotypes.The dominant genotype was X23 (21 strains, 22.3%), of which 18 strains(85.7%) were adult isolates and 3 strains (14.3%) were children isolates.The drug resistance rate of X23 genotypes to carbapenems was 100%, which was significantly higher than that of other genotypes.The results of MLST genotyping showed that X23 genotype was ST195, which belonged to clonal complex(CC92) clone. Conclusions The overall drug resistance rate of Acinetobacter baumannii isolates in Inner Mongolia Medical University Affiliated Hospital was significantly lower than that of adult isolates, and the diversity of genotypes was obvious.The dominant genotypes of the strains belongs to the CC92 clone population, and is the dominant clone strain in many places of our country. Key words: Pediatrics; Acinetobacter baumannii; Drug resistance; Homology analysis