TY - JOUR T1 - Genetic Background of Escherichia coli and Extended-spectrum β-Lactamase Type T2 - Emerging Infectious Disease journal PY - 2005 VL - 11 IS - 1 SP - 54 SN - 1080-6059 AB - To assess the implication of the genetic background of Escherichia coli strains in the emergence of extended-spectrum-β-lactamases (ESBL), 55 TEM-, 52 CTX-M-, and 22 SHV-type ESBL-producing clinical isolates involved in various extraintestinal infections or colonization were studied in terms of phylogenetic group, virulence factor (VF) content (pap, sfa/foc, hly, and aer genes), and fluoroquinolone resistance. A factorial analysis of correspondence showed that SHV type, and to a lesser extent TEM type, were preferentially observed in B2 phylogenetic group strains that exhibited numerous VFs but were fluoroquinolone-susceptible, whereas the newly emerged CTX-M type was associated with the D phylogenetic group strains that lacked VF but were fluoroquinolone-resistant. Thus, the emergence of ESBL-producing E. coli seems to be the result of complex interactions between the type of ESBL, genetic background of the strain, and selective pressures in ecologic niches. KW - Escherichia coli KW - extended-spectrum β-lactamase KW - virulence KW - phylogenetic group KW - fluoroquinolone resistance KW - research KW - France DO - 10.3201/eid1101.040257 UR - https://wwwnc.cdc.gov/eid/article/11/1/04-0257_article ER - End of Reference