Abstract
Objectives: To determine the prevalence and the diversity of extended‐spectrum β‐lactamases (ESBLs) among Escherichia coli isolates in Zhengzhou, China.
Methods: Clinical isolates were collected and investigated from the first affiliated hospital of Zhengzhou University and its associated health‐care facilities in Zhengzhou, China, during the period from January 2006 to June 2008. Antibiograms were performed on Mueller–Hinton agar plates with the disc‐diffusion method and MICs were determined by the agar‐dilution method. Total DNA was extracted with a Qiagen mini kit and screened by PCR.
Results: Of 94 nonduplicate ESBL‐positive isolates, TEM‐type was encoded in 74 and 79% of the ESBL isolates. Fifty‐six isolates were SHV type ESBLs. CTX‐M‐1, CTX‐M‐14, CTX‐M‐25, and CTX‐M‐38 types were encoded in 30, 54, 6, and 4, respectively. OXA‐1‐type β‐lactamases were encoded in six and OXA‐20‐type was encoded in two isolates.
Conclusions: We describe a complex ESBL epidemiology. The study revealed a high rate of ESBL‐producing E. coli isolates. TEM and CTX‐M enzymes dominated in ESBL‐positive E. coli isolates in Zhengzhou, China. J. Clin. Lab. Anal. 23:404–407, 2009. © 2009 Wiley‐Liss, Inc.