[Multiplex PCR assay for dissemination and diversity of extended-spectrum beta-lactamase genes in Shigella isolates]

[[[ Objective: ]]] To develop a rapid and simple multiplex polymerase chain reaction (PCR) method which discriminates extended-spectrum beta-lactamases (ESBLs) genes in sporadic Shigella isolates from 1998 to 2007 in Hangzhou city, China. [[[ Methods: ]]] After ESBLs screening according to the Clinical and Laboratory Standards Institute (CLSI) method, CTX-M, TEM, SHV and OXA-1 encoding genes were detected by using a multiplex PCR method, and the results were verified by 8 single gene PCR amplification. [[[ Results: ]]] Seventeen isolates harbored ESBLs genes among 195 Shigella isolates (8.72%). Genes encoding CTX-M (17 strains), TEM (2 strains), OXA-1 (10 strains) and SHV (0 strains) were discriminated with multiplex PCR analysis, which coincided with eight single gene PCR analysis at 94.12%. [[[ Conclusion: ]]] Multiplex PCR should be a suitable tool for initial rapid screening and discriminating ESBLs genes in Shigella isolates. With similar trend of national surveillance data, the proportion of sporadic Shigella isolates harbouring ESBLs genes might probably be on increase.