OBJECTIVES To establish the prevalence of the AmpC beta-lactamase phenotype in clinical isolates of Escherichia coli and characterize the genetic resistance mechanisms causing the observed phenotype. METHODS Clinical E. coli (n = 74) with reduced susceptibility to third-generation cephalosporins and resistance to cefoxitin were collected from the Department of Clinical Microbiology at Hvidovr...

introduction: this study is aimed to compare phenotypic test methods and determine antibiotic susceptibility pattern of ampc beta-lactamase producing uropathogenic escherichia coli and klebsiella pneumoniae in clinical isolates. method: e. coli and k. pneumoniae were identified by standard microbiological procedures. screening of ampc beta-lactamase production was done by using cefoxitin disc (...

OBJECTIVE To compare the genetic environments of ampC genes in different Acinetobacter baumannii isolates showing different levels of beta-lactam resistance. METHODS The patterns of beta-lactam resistance and beta-lactamase production were investigated for 42 A. baumannii clinical strains. The MICs of various beta-lactams were determined in the presence or absence of the class C cephalosporin...

INTRODUCTION Klebsiella pneumoniae is one of the main opportunistic pathogens which can cause different types of infections. Production of beta-lactamases like AmpC and ESBL mostly lead to beta-lactam resistance in these Gram-Negative bacteria. The aim of this study was the detection of AmpC-producing K. pneumoniae in clinical isolates. MATERIALS AND METHODS Three hundred and three isolates o...

Emergence of antimicrobial resistance amongst uropathogenic Escherichia coli and Klebsiella pneumoniae has become a major public health concern of the 21st century [1]. According to World Health Organization (WHO) report 2014, alarming rates of resistance have been reported in all WHO regions due to resistant pathogens like E. coli, K. pneumoniae and Staphylococcus saprophyticus causing urinary...

BACKGROUND & OBJECTIVE The production of carbapenemases is an important mechanism responsible for the carbapenem resistance. A simple and inexpensive testing method for screening of carbapenemase producers is essential. A prospective study was undertaken to detect metallo-beta-lactamases (MBLs) and AmpC beta-lactamases in nonfermentative Gram negative bacteria and to evaluate the various method...

Acquired resistance is through the production of AmpC Beta Lactamases (AmpC), Extended Spectrum Beta Lactamases (ESBL) and Metallo Beta-Lactamases Enzymes (MBL). Resistance to β-lactam antibiotics is associated with production of ESBL which can hydrolyze oxyimino β-lactams such as cefotaxime, ceftriaxone, ceftazidime and monobactams, however, without any effect on cephamycins, carbapenems and r...

AIM the goal of this study is to understand the phenotype characteristic of beta-lactamase enzymes producing Enterobacteriaceae, such as ESBL, AmpC, and carbapenemase. METHODS three different methods are performed to confirm those phenotypic characteristics, namely double disk diffusion method to confirm ESBL, AmpC disk test (cefoxitin-based) to confirm AmpC, and modified Hodge test to confir...

In members of the family Enterobacteriaceae, ampC, which encodes a beta-lactamase, is regulated by an upstream, divergently transcribed gene, ampR. However, in Pseudomonas aeruginosa, the regulation of ampC is not understood. In this study, we compared the characteristics of a P. aeruginosa ampR mutant, PAOampR, with that of an isogenic ampR+ parent. The ampR mutation greatly altered AmpC produ...

Despite the discovery of novel beta-lactamases such as extended-spectrum beta-lactamases (ESBLs), imported AmpC, and carbapenem-hydrolyzing beta-lactamases at least a decade ago, there remains a low level of awareness of their importance and how to detect them. There is a need to increase the levels of awareness of clinical laboratories about the detection of newer beta-lactamases. Therefore, a...