Abrupt Emergence of a Single Dominant Multidrug-Resistant Strain of Escherichia coli

• Published in: The Journal of infectious diseases Vol. 207; no. 6; pp. 919 - 928
• Main Authors: Johnson, James R., Tchesnokova, Veronika, Johnston, Brian, Clabots, Connie, Roberts, Pacita L., Billig, Mariya, Riddell, Kim, Rogers, Peggy, Qin, Xuan, Butler-Wu, Susan, Price, Lance B., Aziz, Maliha, Nicolas-Chanoine, Marie-Hélène, DebRoy, Chitrita, Robicsek, Ari, Hansen, Glen, Urban, Carl, Platell, Joanne, Trott, Darren J., Zhanel, George, Weissman, Scott J., Cookson, Brad T., Fang, Ferric C., Limaye, Ajit P., Scholes, Delia, Chattopadhyay, Sujay, Hooper, David C., Sokurenko, Evgeni V.
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 15.03.2013
• Subjects: Adhesins, Escherichia coli - genetics; Alleles; Amino acids; Anti-Bacterial Agents - pharmacology; Antimicrobials; BACTERIA; Bacteriology; Biological and medical sciences; Clonal Evolution; DNA Gyrase - genetics; DNA Topoisomerase IV - genetics; DNA, Bacterial - genetics; Drug Resistance, Multiple, Bacterial - genetics; Escherichia coli; Escherichia coli - drug effects; Escherichia coli - genetics; Escherichia coli Infections - drug therapy; Escherichia coli Infections - epidemiology; Escherichia coli Infections - microbiology; Fimbriae Proteins - genetics; Fluoroquinolones; Fluoroquinolones - pharmacology; Fundamental and applied biological sciences. Psychology; Genetic mutation; Humans; Infectious diseases; Major and Brief Reports; Medical research; Medical sciences; Microbiology; Miscellaneous; Molecular Epidemiology; Multilocus Sequence Typing; Phylogenetics; Research grants; Infection; Bacteria; Escherichia coli; Multiple resistance; Enterobacteriaceae; Strain
• ISSN: 0022-1899; 1537-6613; 1537-6613
• DOI: 10.1093/infdis/jis933

Background. Fluoroquinolone-resistant Escherichia coli are increasingly prevalent. Their clonal origins— potentially critical for control efforts—remain undefined. Methods. Antimicrobial resistance profiles and fine clonal structure were determined for 236 diverse-source historical (1967—2009) E. coli isolates representing sequence type ST131 and 853 recent (2010—2011) consecutive E. coli isolates from 5 clinical laboratories in Seattle, Washington, and Minneapolis, Minnesota. Clonal structure was resolved based on fimH sequence (fimbrial adhesin gene: H subclone assignments), multilocus sequence typing, gyrA and parC sequence (fluoroquinolone resistance-determining loci), and pulsed-field gel electrophoresis. Results. Of the recent fluoroquinolone-resistant clinical isolates, 52% represented a single ST131 subclonal lineage, H30, which expanded abruptly after 2000. This subclone had a unique and conserved gyrA/parC allele combination, supporting its tight clonality. Unlike other ST131 subclones, H30 was significantly associated with fluoroquinolone resistance and was the most prevalent subclone among current E. coli clinical isolates, overall (10.4%) and within every resistance category (11%—52%). Conclusions. Most current fluoroquinolone-resistant E. coli clinical isolates, and the largest share of multidrug-resistant isolates, represent a highly clonal subgroup that likely originated from a single rapidly expanded and disseminated ST131 strain. Focused attention to this strain will be required to control the fluoroquinolone and multi-drug-resistant E. coli epidemic.