title: What's new in antibiotic resistance? Focus on beta-lactamases.
abstract: In gram-negative bacteria, beta-lactamases are the most important mechanism of resistance to beta-lactam antibiotics. Currently, the beta-lactamases receiving the most attention are the extended-spectrum beta-lactamases (ESBLs), inhibitor-resistant beta-lactamases and carbapenemases. When found in Escherichia coli and Klebsiella spp., ESBLs confer resistance to extended-spectrum cephalosporins, such as ceftazidime, cefotaxime and cefepime. Hence, ESBLs limit the choice of beta-lactam therapy to carbapenems. A worrisome trend is the increasing number of pathogens found in isolates from patients in the community that possess ESBLs. It is equally distressing that carbapenemases (serine and metallo-beta-lactamases) are being found in many of the same bacteria that harbor ESBLs, for example Klebsiella pneumoniae. Despite many years studying beta-lactamases, important clinical and scientific questions still remain.
authors.affiliation: Division of Infectious Diseases, Department of Medicine, University Hospitals of Cleveland, USA.
authors.forename: Maja
authors.initials: M
authors.lastname: Babic
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Hujer
authors.forename: Robert A
authors.initials: RA
authors.lastname: Bonomo
mesh_terms: D000818:Animals; D001419:Bacteria / Q000187:drug effects* / Q000201:enzymology* / Q000235:genetics; D001424:Bacterial Infections / Q000188:drug therapy / Q000382:microbiology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D024881:Drug Resistance, Bacterial / Q000502:physiology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D008826:Microbial Sensitivity Tests; D010957:Plasmids / Q000235:genetics; D065093:beta-Lactamase Inhibitors; D001618:beta-Lactamases / Q000145:classification / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D047090:beta-Lactams / Q000494:pharmacology
chemical_list: D001426:Bacterial Proteins; D004791:Enzyme Inhibitors; D065093:beta-Lactamase Inhibitors; D047090:beta-Lactams; C048795:AmpC beta-lactamases; D001618:beta-Lactamases; C063912:carbapenemase