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...

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conclusions the prevalence of esbl-producing klebsiella strains in shahid-beheshti hospital in kashan has increased. the study concluded that there was a high prevalence of the blactx-m type gene among esbl positive isolates. patients and methods one hundred klebsiella spp. were isolated from clinical specimens of hospitalized patients at shahid-beheshti hospital from december 2012 to november ...

conclusions this study showed that multiple β-lactamases can be produced in burn isolates. this suggests that use of cephalosporins and carbapenems should be restricted in burn isolates to minimize the development and spread of these multidrug resistant pathogens. results there was 99% resistance to carbenicillin, and ticarcillin, 98% to cotrimoxazole, 96% to ciprofloxacin, and aztreonam, 95% t...

INTRODUCTION The rising prevalence of extended-spectrum beta-lactamases in gram-negative bacillary pathogens is an important clinical problem resulting from the extensive use of broad-spectrum antibiotics. The emergence of the extended-spectrum beta-lactamases increases the possibility that traditional, empiric antimicrobial regimens may be ineffective. The aims of this study are: to determine ...

Clavulanic acid, sulbactam, and tazobactam are inhibitors of a variety of plasmid-mediated beta-lactamases. However, inhibition data for these three inhibitors with a wide range of different plasmid-mediated beta-lactamases have not yet been compared under the same experimental conditions. A number of groups have inferred that clavulanic acid inhibits extended-spectrum TEM and SHV beta-lactamas...

Multidrug resistance has been increasing among Gram-negative bacteria and is strongly associated with the production of both chromosomal- and plasmid-encoded beta-lactamases, whose number now exceeds 890. Many of the newer enzymes exhibit broad-spectrum hydrolytic activity against most classes of beta-lactams. The most important plasmid-encoded beta-lactamases include (a) AmpC cephalosporinases...