Resistance in Escherichia coli isolates colonizing gastrointestinal tracts of dogs, cats, and their owners in Northern Kenya was investigated with an emphasis on extended-spectrum beta-lactamases (ESBLs). Totals of 47 (22%, n = 216), 2 (4%, n = 50), and 4 (17%, n = 23) CTX-M-15-producing E. coli isolates were obtained from dogs, cats, and humans, respectively. CTX-M-15-producing E. coli isolate...

Resistance in Gram-negative bacteria has been increasing, particularly over the last 6 years. This is mainly due to the spread of strains producing extended-spectrum β-lactamases (ESBLs) such as CTX-M enzymes or AmpC β-lactamases. Many of the isolates producing these enzymes are also resistant to trimethoprim, quinolones and aminoglycosides, often due to plasmid co-expression of other resistanc...

Extended-spectrum β-lactamases (ESBLs) and AmpC β-lactamases are plasmid (but also chromosomally) encoded enzymes found in Enterobacteriaceae, determining resistance to a variety of important antibiotics including penicillins, cephalosporins, and monobactams. In recent decades, the prevalence of ESBL/AmpC-producing bacteria has increased rapidly across the world. Here, we evaluate the potential...

BACKGROUND NXL104 potentiates ceftazidime and ceftaroline against Enterobacteriaceae with extended-spectrum, AmpC, KPC and OXA β-lactamases. We examined whether similar potentiation was obtained against non-fermenters, which are less permeable than Enterobacteriaceae and have more potent efflux. METHODS MICs of ceftazidime+NXL104 (with NXL104 at 4 mg/L) and comparators were determined by CLSI...

Carbapenemases are a large and diverse family of microbial enzymes that hydrolyze not only carbapenems but also other b-lactams, with the occasional exception of monobactams, such as aztreonam. For clinicians, the nomenclature of carbapenemases, like that of other b-lactamases, is confusing. In keeping with other b-lactamases, carbapenemases can be classified on the basis of function or structu...

While Frye and Jackson do a good job describing the common mechanisms of resistance found in food animals in the U.S., they err in stating that in the U.S. extended spectrum β-lactamases (ESBLs) “thus far have only been found in human and not food animal isolates.” In fact, Wittum et al., in 2010 first reported the collection of Escherichia coli expressing CTX-M-type ESBLs in fecal isolates fro...

Ceftazidime-avibactam has activity against Pseudomonas aeruginosa and Enterobacteriaceae expressing numerous class A and class C β-lactamases, although the ability to inhibit many minor enzyme variants has not been established. Novel VEB class A β-lactamases were identified during characterization of surveillance isolates. The cloned novel VEB β-lactamases possessed an extended-spectrum β-lacta...

Extended spectrum beta-lactamases (ESBLs) are enzymes produced by bacteria, mostly members of the family Enterobacteriaceae commonly Escherichia coli and Klebsiella pneumoniae. ESBLs hydrolyze beta-lactam ring antibiotics making these ineffective therefore rendering bacteria resistance against antibiotics. The global upsurge producing causing both hospital community acquired infections urinary ...

BACKGROUND Pseudomonas aeruginosa is a leading cause of nosocomial infections worldwide. Resistance of P. aeruginosa strains to the broad-spectrum cephalosporins may be caused by extended-spectrum β-lactamases (ESBLs). OBJECTIVES The aim of this study was to determine the antimicrobial resistance patterns and prevalence of PER-1 and VEB-1 type genes among ESBL producing strains of P. aerugino...

BACKGROUND AND OBJECTIVES Klebsiella pneumoniae, one of the important causes of nosocomial infections, is the most common extended spectrum β-lactamases (ESBLs) producing organism. ESBLs are defined as the enzymes capable of hydrolyzing oxyimino-cephalosporins, monobactams and carbapenems. The aims of this study were to identify ESBL-producing K. pneumoniae isolates and detect their antibiotic ...