Characteristics of Extended-Spectrum β-Lactamases-Producing Escherichia coli in Fecal Samples of Inpatients of Beijing Tongren Hospital.

We aimed to investigate the prevalence of extended-spectrum β-lactamases (ESBL)-producing Escherichia coli in Beijing Tongren hospital and to identify a possible relation between colonization and infection. The clinical data on 650 inpatients between March 2012 and July 2012 were retrospectively reviewed. The prevalence of ESBL-producing E. coli among the inpatients was 25.7% (167/650), with the highest level (50.0%) in the rheumatology ward and the lowest (10.0%) in intensive care units. Hospital stay more than 2 years prior to infection, the use of antibiotics within 3 months of infection, and the use of glucocorticoids or immunosuppressive drugs were found to be significantly associated with carriage of ESBL-producing E. coli (P < 0.05). In total, 76 sequence types (STs) were revealed by multilocus sequence typing. ST38 (n = 12, 7.2%) was the most common ST, followed by ST10 (n = 10, 6.0%) and ST131 and ST167 (n = 9 and 5.4% each). Among the fecal carriers, only one patient had an active infection, which was caused by an ST38 strain. In conclusion, in Beijing Tongren hospital, the prevalence of ESBL-producing E. coli was not high. The risk factors of carriage of ESBL-producing E. coli are hospitalization and use of antibiotics, glucocorticoids, or immunosuppressive drugs. ST38, ST10, ST131, and ST167 are the prominent genotypes, but almost 50.0% of STs were scarcely distributed.