Escherichia coli sequence type 131 (ST131) subclone H30 as an emergent multidrug-resistant pathogen among US veterans.
Publication/Presentation Date
11-1-2013
Abstract
BACKGROUND: Escherichia coli sequence type 131 (ST131), typically fluoroquinolone-resistant (FQ-R) and/or extended-spectrum β-lactamase (ESBL)-producing, has emerged globally. We assessed its prevalence and characteristics among US veterans.
METHODS: In 2011, 595 de-identified E. coli clinical isolates were collected systematically within 3 resistance groups (FQ-susceptible [FQ-S], FQ-R, and ESBL-producing) from 24 nationally distributed Veterans Affairs Medical Centers (VAMCs). ST131 and its H30 subclone were detected by polymerase chain reaction and compared with other E. coli for molecular traits, source, and resistance profiles.
RESULTS: ST131 accounted for 78% (184/236) of FQ-R and 64.2% (79/123) of ESBL-producing isolates, but only 7.2% (17/236) of FQ-S isolates (P < .001). The H30 subclone accounted for ≥95% of FQ-R and ESBL-producing, but only 12.5% of FQ-S, ST131 isolates (P < .001). By back-calculation, 28% of VAMC E. coli isolates nationally represented ST131. Overall, ST131 varied minimally in prevalence by specimen type, inpatient/outpatient source, or locale; was the most prevalent ST, followed distantly by ST95 and ST12 (13% each); and accounted for ≥40% (β-lactams), >50% (trimethoprim-sulfamethoxazole , multidrug), or >70% (ciprofloxacin, gentamicin) of total antimicrobial resistance. FQ-R and ESBL-producing ST131 isolates had higher virulence scores than corresponding non-ST131 isolates. ST131 pulsotypes overlapped extensively among VAMCs.
CONCLUSIONS: Among US veterans, ST131, primarily its H30 subclone, accounts for most antimicrobial-resistant E. coli and is the dominant E. coli strain overall. Possible contributors include multidrug resistance, extensive virulence gene content, and ongoing transmission. Focused attention to ST131, especially its H30 subclone, could reduce infection-related morbidity, mortality, and costs among veterans.
Volume
57
Issue
9
First Page
1256
Last Page
1265
ISSN
1537-6591
Published In/Presented At
Colpan, A., Johnston, B., Porter, S., Clabots, C., Anway, R., Thao, L., Kuskowski, M. A., Tchesnokova, V., Sokurenko, E. V., Johnson, J. R., & VICTORY (Veterans Influence of Clonal Types on Resistance: Year 2011) Investigators (2013). Escherichia coli sequence type 131 (ST131) subclone H30 as an emergent multidrug-resistant pathogen among US veterans. Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 57(9), 1256–1265. https://doi.org/10.1093/cid/cit503
Disciplines
Medicine and Health Sciences
PubMedID
23926176
Department(s)
Department of Medicine
Document Type
Article