TITLE

Molecular characterization of CTX-M ²-lactamases among Klebsiella pneumoniae isolated from patients at Tehran hospitals

AUTHOR(S)
N Shoeib; S Fereshteh; FM Mehdi; NV Sadat; N Leila
PUB. DATE
July 2011
SOURCE
Indian Journal of Medical Microbiology;Jul2011, Vol. 29 Issue 3, p254
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Purpose: Plasmid-encoded CTX-M-group of extended-spectrum â-lactamases (ESBLs) represent a significant and rapidly emerging problem in most part of the world. The aim of the present study was to describe the prevalence of CTX-M producing Klebsiella pneumoniae at Tehran hospitals. Materials and Methods: Clinical isolates of K. pneumoniae (n=250) were collected from 10 hospitals of Tehran. Susceptibility to antimicrobial agents, MIC of cefotaxime and ESBLs production of collected isolates were detected. All ESBL producing isolates were screened for blaCTX-M genes using PCR and DNA sequencing. Molecular typing of blaCTX-M harboring isolates was performed by Pulsed-field gel electrophoresis assay. Results: Of 250 K. pneumoniae clinical isolates, 102 isolates revealed ESBLs-phenotype. PCR assay and sequencing detected blaCTX-M genes in 71.5% (n= 73) of ESBL-producing isolates. The prevalence of CTX-M -I and CTX-M-III clusters among these isolates was 35.61% (n=26) and 21.9 % (n=16) respectively. Coexistence of CTX-M -I and CTX-M-III clusters was found among 42.5% (n= 31) of isolates. Of 102 isolates that were positive in the phenotypic confirmatory test (PCT), 29 isolates (28.4%) did not produce any amplicons in PCR for blaCTX-M gene. The results of PCR for CTX-M -II and CTX-M-IV clusterswere also negative. Analysis of the 31 CTX-M producing K. pneumoniae isolates by PFGE typing showed 26 distinct patterns. Conclusions: The blaCTX-M genes are widespread among Iranian isolates of K. pneumoniae. PFGE demonstrated the high diversity of K. pneumoniae harboring blaCTX-M in our study.
ACCESSION #
65286919

 

Related Articles

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics