AIMS AND OBJECTIVES With the relentless increase in multidrug- and extensively-drug resistant tuberculosis (MDR/XDR-TB), new treatment strategies are necessary. Favorable results have been reported by combining a β-lactam antibiotic and a β-lactamase inhibitor. The β-lactamase encoded by the blaC gene of Mycobacterium tuberculosis (MTB) is the major mechanism of resistance to β-lactam antibioti...

The AmpC β-lactamases are clinically important because they confer resistance to the narrow-, expandedand the broad-spectrum cephalosporins, the β-lactam-β-lactamase inhibitor combinations and aztreonam. The clinical microbiology laboratories should be able to detect the bacterial strains which produce AmpC, since these strains may appear to be susceptible to a particular β-lactam antibiotic in...

OBJECTIVES A relapse from Escherichia coli bloodstream infection was observed in a patient with acute leukaemia treated with ceftazidime for 7 days for febrile neutropenia. Whereas the original E. coli isolate was resistant to β-lactam/β-lactamase inhibitor combinations (EC1), the relapse E. coli isolate showed a similar phenotype but with resistance extended to ceftazidime (EC2). We investigat...

conclusions the β-lactamase disk test is appropriately sensitive to detect esbls in mdr isolates of e. coli. background most urinary tract infections (utis) are caused by escherichia coli (e. coli) species. due to infections outbreaks of e. coli strains with multiple mechanisms of resistance to β-lactam antibiotics, the sensitivity of confirmatory tests to detect the extended spectrum β-lactama...

background and objectives: pseudomonas aeruginosa is a frequent opportunistic pathogen in health care associated infections that is highly resistant to the majority of β-lactams. the aims of this study were to access the antimicrobial susceptibility pattern of p. aeruginosa isolated from educational hospitals of qazvin and alborz provinces, to determine the prevalence of metallo-β-lactamase (mb...

KPC-2 is the most prevalent class A carbapenemase in the world. Previously, KPC-2 was shown to hydrolyze the β-lactamase inhibitors clavulanic acid, sulbactam, and tazobactam. In addition, substitutions at amino acid position R220 in the KPC-2 β-lactamase increased resistance to clavulanic acid. A novel bridged diazabicyclooctane (DBO) non-β-lactam β-lactamase inhibitor, avibactam, was shown to...

Several antimicrobial agents are being investigated as alternatives to carbapenems in the treatment of infections caused by ESBL-producing Enterobacteriaceae, which may be useful in avoiding overuse of carbapenems in the context of recent global spread of carbapenem-resistant Enterobacteriaceae. The most promising candidates for invasive infections so far are β-lactam/β-lactamase inhibitor comb...

Carbapenem resistance caused by metallo-β-lactamases is a serious global challenge that, if not tackled efficiently, expected to lead millions of deaths in the coming decades. Verona-integron encoded metallo-β-lactamase 2 (VIM-2) bacterial enzyme that has been reported from multidrug-resistant nosocomial isolates Pseudomonas aeruginosa and other Gram-negative pathogens. As it hydrolyzes most β-...

Ceftazidime-avibactam is the first antimicrobial approved by the U.S. FDA for the treatment of carbapenem-resistant Enterobacteriaceae. Avibactam, a non-β-lactam β-lactamase inhibitor, inactivates class A serine carbapenemases, including Klebsiella pneumoniae carbapenemase (KPC). We report a KPC-producing K. pneumoniae isolate resistant to ceftazidime-avibactam (MIC, 32/4 μg/ml) from a patient ...