Routine detection of AmpC beta lactamases in Escherichia coli is cumbersome. This study was performed to determine the usefulness of a modified disc diffusion test to detect AmpC beta lactamases in E.coli. 28 non-repetitive, cefoxitin resistant isolates of E.coli were collected from cases of urinary tract infections and screened phenotypically for ESBLs and AmpC beta lactamase using DDST (cefta...

Microbial drug resistance is a growing problem of global magnitude. In gram-negative pathogens, the most important resistance problems are encountered in Enterobacteriaceae, Pseudomonas aeruginosa and Acinetobacter, with increasing trends observed for all major anti-gram-negative agents (beta-lactams, fluoroquinolones and aminoglycosides). A matter of major concern is the emergence of new beta-...

Respiratory isolates of Klebsiella pneumoniae in Korea during 2002-2003 were studied to determine the prevalence and types of extended-spectrum beta-lactamases (ESBLs) and plasmid-mediated AmpC beta-lactamases (PABLs). ESBL-production was tested by double-disk synergy, and genotypes of beta-lactamases were determined by PCR and sequencing. ESBLs were detected in 28.4% of 373 isolates, and the m...

Many clinical laboratories have problems detecting extended-spectrum beta-lactamases (ESBLs) and plasmid-mediated AmpC beta-lactamases. Confusion exists about the importance of these resistance mechanisms, optimal test methods, and appropriate reporting conventions. Failure to detect these enzymes has contributed to their uncontrolled spread and sometimes to therapeutic failures. Although Natio...

results of the 100 klebsiella isolates, 41 (41%) demonstrated resistance or reduced susceptibility to ceftazidime and/or aztreonam and 35% (n = 35) were esbl-producers. twenty-eight (8o%) of the esbl-producing isolates carried the blactx-m type genes. based on pcr assays and sequencing of blactx-m genes, ctx-m-1, ctx-m-2 and ctx-m-9 were identified in 21 (60%), 15 (42%) and nine (34%) of these ...

Despite the recent global spread of CTX-M beta-lactamases in Escherichia coli isolates from community-acquired urinary tract infections (CA-UTIs), their dissemination has been little studied in developing countries. In a 2-year prospective study, we documented the prevalence of extended-spectrum beta-lactamases (ESBLs) in E. coli that were responsible for CA-UTIs in Phnom-Penh, Cambodia. Ninety...

OBJECTIVES The aim of this study was to investigate the presence of PER-1-type ESBLs in drug resistant Pseudomonas aeruginosa isolates. MATERIALS AND METHODS During one-year period (2008-2009), following isolation and identification of 56 P. aeruginosa, the E-test method was performed for determination of minimal inhibitory concentration of ceftazidim. The isolates that they had MIC≥16 µg/ml ...

Objective(s) Resistance to the new generation of cephalosporins which is mediated by Extended-Spectrum beta-lactamases (ESBLs) has been found among Escherichia coli isolates throughout the world. These resistance genes and their producers, the micro-organisms carrying beta-lactamases, are responsible for serious clinical and therapeutic problems among inpatients and it is necessary to pay more...

A total of 23 clinical isolates (15 Escherichia coli and 8 Klebsiella pneumoniae), resistant to cefotaxime and ceftazidime recovered during 2002 and 2003, were investigated for production of CTX-M extended spectrum beta-lactamase (ESBL) by phenotypic and molecular methods. The presence of ESBL was tested by NCCLS phenotypic confirmatory test using cephalosporin/clavulanate combination discs and...