Format

Send to

Choose Destination
Antimicrob Agents Chemother. 2015;59(6):3424-32. doi: 10.1128/AAC.00270-15. Epub 2015 Mar 30.

Clinical epidemiology and molecular analysis of extended-spectrum-β-lactamase-producing Escherichia coli in Nepal: characteristics of sequence types 131 and 648.

Author information

1
Department of Clinical Microbiology, Kathmandu University School of Medical Sciences, Dhulikhel, Nepal.
2
Disease Control and Prevention Center, National Center for Global Health and Medicine, Tokyo, Japan kayokohayakawa@gmail.com.
3
Pathogenic Microbe Laboratory, Research Institute, National Center for Global Health and Medicine, Tokyo, Japan.
4
Disease Control and Prevention Center, National Center for Global Health and Medicine, Tokyo, Japan.
5
Department of Infectious Diseases, Research Institute, National Center for Global Health and Medicine, Tokyo, Japan.
6
Disease Control and Prevention Center, National Center for Global Health and Medicine, Tokyo, Japan Department of Infectious Diseases, Research Institute, National Center for Global Health and Medicine, Tokyo, Japan.
7
Department of International Medical Cooperation, National Center for Global Health and Medicine, Tokyo, Japan.
8
Public Health Research Laboratory, Institute of Medicine, Tribhuvan University Teaching Hospital, Kathmandu, Nepal.

Abstract

Recently, CTX-M-type extended-spectrum-β-lactamase (ESBL)-producing Escherichia coli strains have emerged worldwide. In particular, E. coli with O antigen type 25 (O25) and sequence type 131 (ST131), which is often associated with the CTX-M-15 ESBL, has been increasingly reported globally; however, epidemiology reports on ESBL-producing E. coli in Asia are limited. Patients with clinical isolates of ESBL-producing E. coli in the Tribhuvan University teaching hospital in Kathmandu, Nepal, were included in this study. Whole-genome sequencing of the isolates was conducted to analyze multilocus sequence types, phylotypes, virulence genotypes, O25b-ST131 clones, and distribution of acquired drug resistance genes. During the study period, 105 patients with ESBL-producing E. coli isolation were identified, and the majority (90%) of these isolates were CTX-M-15 positive. The most dominant ST was ST131 (n = 54; 51.4%), followed by ST648 (n = 15; 14.3%). All ST131 isolates were identified as O25b-ST131 clones, subclone H30-Rx. Three ST groups (ST131, ST648, and non-ST131/648) were compared in further analyses. ST648 isolates had a proportionally higher resistance to non-β-lactam antibiotics and featured drug-resistant genes more frequently than ST131 or non-ST131/648 isolates. ST131 possessed the most virulence genes, followed by ST648. The clinical characteristics were similar among groups. More than 38% of ESBL-producing E. coli isolates were from the outpatient clinic, and pregnant patients comprised 24% of ESBL-producing E. coli cases. We revealed that the high resistance of ESBL-producing E. coli to multiple classes of antibiotics in Nepal is driven mainly by CTX-M-producing ST131 and ST648. Their immense prevalence in the communities is a matter of great concern.

PMID:
25824221
PMCID:
PMC4432170
DOI:
10.1128/AAC.00270-15
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center