title: Carbapenemase-Producing Klebsiella pneumoniae, a Key Pathogen Set for Global Nosocomial Dominance.
abstract: The management of infections due to Klebsiella pneumoniae has been complicated by the emergence of antimicrobial resistance, especially to carbapenems. Resistance to carbapenems in K. pneumoniae involves multiple mechanisms, including the production of carbapenemases (e.g., KPC, NDM, VIM, OXA-48-like), as well as alterations in outer membrane permeability mediated by the loss of porins and the upregulation of efflux systems. The latter two mechanisms are often combined with high levels of other types of β-lactamases (e.g., AmpC). K. pneumoniae sequence type 258 (ST258) emerged during the early to mid-2000s as an important human pathogen and has spread extensively throughout the world. ST258 comprises two distinct lineages, namely, clades I and II, and it seems that ST258 is a hybrid clone that was created by a large recombination event between ST11 and ST442. Incompatibility group F plasmids with blaKPC have contributed significantly to the success of ST258. The optimal treatment of infections due to carbapenemase-producing K. pneumoniae remains unknown. Some newer agents show promise for treating infections due to KPC producers; however, effective options for the treatment of NDM producers remain elusive.
authors.affiliation: Division of Microbiology, Calgary Laboratory Services, University of Calgary, Calgary, Alberta, Canada Department of Pathology and Laboratory Medicine, University of Calgary, Calgary, Alberta, Canada Department of Microbiology, Immunology, and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada Department of Medical Microbiology, University of Pretoria, Pretoria, South Africa johann.pitout@cls.ab.ca.
authors.forename: Johann D D
authors.initials: JD
authors.lastname: Pitout
authors.affiliation: Medical and Molecular Microbiology Unit Emerging Antibiotic Resistance, Department of Medicine, Faculty of Science, University of Fribourg, Fribourg, Switzerland HFR-Hôpital Cantonal, Fribourg, Switzerland.
authors.forename: Patrice
authors.initials: P
authors.lastname: Nordmann
authors.affiliation: HFR-Hôpital Cantonal, Fribourg, Switzerland.
authors.forename: Laurent
authors.initials: L
authors.lastname: Poirel
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D015780:Carbapenems / Q000494:pharmacology; D002999:Clone Cells; D003227:Conjugation, Genetic; D003428:Cross Infection / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D004251:DNA Transposable Elements; D015964:Gene Expression Regulation, Bacterial; D006801:Humans; D007710:Klebsiella Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000201:enzymology / Q000235:genetics* / Q000472:pathogenicity; D010957:Plasmids / Q000737:chemistry / Q000378:metabolism; D018272:Porins / Q000172:deficiency / Q000235:genetics; D011995:Recombination, Genetic; D018440:beta-Lactam Resistance / Q000235:genetics*; D001618:beta-Lactamases / Q000235:genetics* / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015780:Carbapenems; D004251:DNA Transposable Elements; D018272:Porins; D001618:beta-Lactamases; C063912:carbapenemase