Characteristics of ESBLs-positive Acinetobacter strains in children with and without diarrhea
- Author:
ZHANG Yuan
;
WANG Mengyu
;
LI Zhenpeng
- Publication Type:Journal Article
- Keywords:
ESBL;
Acinetobacter species;
children with diarrhea;
children without diarrhea;
drug-resistance
- From:
China Tropical Medicine
2024;24(11):1301-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To analyze the drug resistance, genomic information, and genetic relationships of Extended-Spectrum β-Lactamases (ESBLs)-positive Acinetobacter strains colonized in the intestinal tract of children with and without diarrhea, and to explore the carrying status and distinguishing features of two group ESBLs-positive Acinetobacter strains. Methods A total of 842 fresh fecal samples were collected from children with and without diarrhea from a hospital in Shanghai, 2017-2019. ESBLs-resistant Acinetobacter strains were isolated and identified, followed by a drug sensitivity test and whole genome sequencing. A phylogenetic tree was constructed to explore the genetic relationship between Acinetobacter baumannii strains in this study and those isolated in China during the same period. Results A total of 13 ESBLs-positive Acinetobacter strains were isolated, including 11 strains in the diarrhea group and two strains in the non-diarrhea group, the positive rate of ESBLs strains in the diarrhea group was significantly higher than that in the non-diarrhea group (χ2=5.206, P=0.023). All strains showed a high resistance rate to the first-generation cephalosporins (100.0%) and the second-generation cephalosporins (100.0%), with a multidrug resistance rate of 53.8% (7/13). There was no significant difference in the rates of resistance to individual antibiotics and multidrug resistance between the two groups (P>0.05). The blaOXA resistance gene was carried by all strains on the chromosome, which encode enzymes that hydrolyze clinically important antibiotics such as third-generation cephalosporins and carbapenems. Adhesion-type virulence genes were carried by 92.3% (12/13) of the strains, and secretion-type virulence genes were present in 84.6% (11/13). Furthermore, 92.3% (12/13) of ESBLs-positive Acinetobacter strains carried plasmids, with one A. baumannii strain isolated from a non-diarrhea child carrying seven types of plasmids. The analysis of the phylogenetic relationship indicated that A. baumannii strains isolated in this study formed a clonal cluster, and also clustered with some strains from southern China during the same period. Conclusions ESBLs-positive Acinetobacter strains isolated from children with and without diarrhea exhibited serious drug resistance, carrying multiple resistance and virulence genes, as well as multiple plasmids. Carrying multiple plasmids may facilitate the horizontal transmission risk of drug-resistance genes and virulence genes, indicating the need to pay attention to the characteristics of intestinal colonized ESBLs-positive Acinetobacter strains in children and strengthen the monitoring of drug-resistant bacteria colonized in the intestine in healthy children.
- Full text:20251112095823990532.Characteristics of ESBLs-positive Acinetobacter strains in children with and without diarrhea.pdf
