Background and Objective: Beta-lactamases are the most important factors in the resistance to beta-lactam antibiotics among gram-negative bacteria, especially Klebsiella pneumoniae. Nowadays, the prevalence of infections caused by extended-spectrum β-lactamases (ESBLs)-producing K. pneumoniae is increasing, as one of the emerging health problems throughout the world. This study aimed to investi...

Background & objectives: Extended spectrum β-lactamases (ESBLs) are often plasmid mediated derived from mutations in the classic TEM and SHV genes by one or more amino acid substitution around the active site. Detection of TEM and SHV genes by molecular methods in ESBL producing bacteria and their pattern of antimicrobial resistance can provide useful information about its epidemiology and risk...

Introduction / objectives Antimicrobial resistance among nosocomial pathogens is a significant problem in most clinical settings adding to the cost of medical care and the morbidity and mortality of patients. Enterobacteriaceae carrying extended spectrum b-lactamases(ESBLs), Vancomycin resistant Enterococcus (VRE), methicillin resistant Staphylococcus aureus (MRSA) have emerged as significant p...

Methods The present study was performed at four tertiary care hospitals in Isfahan, Iran. During a 14 month period (Jun, 7,2008 to July,6 ,2010).690 of E.coli isolated from urinary tract infection were studied. 425 of E.coli isolated from community acquired and 265 isolated from nosocomial urinary tract infection were evaluated. Standard microbiological methods were performed(according to CLSI...

CTX-M enzymes, the plasmid-mediated cefotaximases, constitute a rapidly growing family of extended-spectrum β-lactamases (ESBLs) with significant clinical impact. CTX-Ms are found in at least 26 bacterial species, particularly in Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis. At least 109 members in CTX-M family are identified and can be divided into seven clusters based on thei...

Proteus mirabilis is a specific opportunistic pathogen of many infections including urinary tract (UTIs). Risk factors are linked with the acquisition multidrug-resistant (MDR) to 3 or more classes antimicrobials) strains. The resistance in extended-spectrum alpha-lactamase rare, but rising beta-lactamase (ESBL) producing strains matter concern. ?-lactamases and antibiotic modifying enzymes mai...

An extended-spectrum B-lactamase (ESBL)-producing Providencia stuartii isolate was studied. A qnrA1 gene co-expressing blaVEB-1 gene was detected. Both genes were transferred to the recipient strain. The ciprofloxacin MIC of recipient strain increased tenfold. The blaVEB-1 gene persisted in microorganisms in Turkey but it also spread with PMQR genes to other species. The combination of PMQR wit...

Wild birds are important indicators and potential spreaders of antibiotic resistance. The order Passerines is scarcely studied apart from Corvus sp. but extended spectrum beta-lactamases (ESBLs) has been found in Blackbirds. We tested 300 fecal samples from a well-studied population of Collared Flycatchers (Ficedula albicollis) at the Island of Gotland in Sweden and found no ESBL-producing bact...

Escherichia coli is a common cause of infections in companion animals. In recent years the increasing prevalence of resistance to β-lactams, including extended-spectrum cephalosporins, antimicrobials frequently used in small animal veterinary practice, was observed in canine isolates of E. coli. The aim of this study was to detect and to characterize extended-spectrum β-lactamases (ESBLs) produ...

Salmonella spp. producing extended-spectrum beta-lactamases (ESBLs) have been reported in many countries, but there is no information on their prevalence in Africa. ESBL-producing Salmonella enterica serotype Isangi and S. enterica serotype Typhimurium strains have been noted in South Africa since 2001. A total of 160 consecutive isolates of Salmonella spp. were collected from 13 hospitals loca...