Virulence Factors of <i>E. coli</i> ST131 and Its H30 and H30Rx Subclones Among Extended-Spectrum Beta-Lactamase Producing Isolates

Abstract

<i>Escherichia coli</i> sequence type 131 (ST131) is a pandemic clone causing predominantly community and hospital-onset antimicrobial-resistant infections. Recently, H30-Rx subclone of <i>E. coli</i> has been disseminated among ST131 strains in combination with beta lactamase subtype CTX-15that may play a role in the prevalence of antibiotic resistance among <i>E. coli</i> strains that cause extra-intestinal infections. This study has been done to investigate the virulence factors of ST131 with their subclones: H30-Rx and non H30-Rx strains. A hundred <i>E. coli</i> isolates which were isolated from different clinical samples were collected from K.R hospital, Mysore. Polymerase chain reaction (PCR) method was used to investigate 19 of the virulence factors among <i>E. coli</i> stains. Out of 100 <i>E. coli</i> strains, 87 of the isolates belonged to ST131, 24 isolates belonged to H30 subclone, and 22/24 (91.7%) belonged to H30-Rx subcolne. ST131 strains harbored high virulence factors more than non ST131 strains and the differences between them were significant for <i>papC</i>, <i>papEF</i> and <i>fyuA</i> genes. All H30-Rx strains were positive for <i>iutA</i> and <i>fimH</i>, however, 95.5% and 81.8% of H30-Rx strains were positive for <i>fyuA</i> and <i>kpsMII</i> respectively and the differences between H30-Rx and non H30-Rx strains were significant for those genes. There are no more reports about H30 and H30-Rx subclones of ST131 <i>E. coli</i> in India. Further studies should be done to investigate the prevalence of ST131 in different places in India and to highlight the other virulence factors to control the dissemination of ST131 clone.