title: Colistin- and carbapenem-resistant Klebsiella oxytoca harboring blaVIM-2and an insertion in the mgrB gene isolated from blood culture.
abstract: A carbapenemase-producing colistin-resistant Klebsiella oxytoca isolate was recovered from a blood culture of a female patient without previous report of risk factors to obtain multidrug-resistant Gram-negative bacilli. A combination of biochemical and molecular methods was used to identify the resistance mechanism of this isolate. Carbapenemase production was mediated by Verona integron-encoded metallo-β-lactamase (VIM)-2. Colistin resistance was not due to plasmid- borne mcr-1 gene, but we found an integration of IS5-like sequence in the mgrB gene of K. oxytoca. This gene is known to be an important regulator of the PhoPQ two-component system, and the disruption of this gene is most likely the cause of lipid A modification resulting in colistin resistance of our isolate. To the best of our knowledge this constitutes the first report of a carbapenemase-producing K. oxytoca with colistin resistance, a case that demonstrates the limited treatment options for infections with multidrug-resistant organisms.
authors.affiliation: Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, Regensburg, Germany.
authors.forename: Michaela
authors.initials: M
authors.lastname: Simon
authors.affiliation: Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, Regensburg, Germany.
authors.forename: Holger
authors.initials: H
authors.lastname: Melzl
authors.affiliation: Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, Regensburg, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Hiergeist
authors.affiliation: Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, Regensburg, Germany.
authors.forename: Katharina
authors.initials: K
authors.lastname: Richert
authors.affiliation: Institute of Medical Microbiology, Justus Liebig University Giessen and German Center for Infection Research, Partner site Giessen-Marburg-Langen, Giessen, Germany.
authors.forename: Linda
authors.initials: L
authors.lastname: Falgenhauer
authors.affiliation: Division of Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, Robert Koch Institute, Wernigerode Branch, Wernigerode, Germany.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Pfeifer
authors.affiliation: Project Group 5, Robert KochInstitute, Wernigerode Branch, Wernigerode, Germany.
authors.forename: Roman G
authors.initials: RG
authors.lastname: Gerlach
authors.affiliation: Department of Neurology, University Hospital Regensburg, Regensburg, Germany.
authors.forename: Kornelius
authors.initials: K
authors.lastname: Fuchs
authors.affiliation: Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, Regensburg, Germany.
authors.forename: Udo
authors.initials: U
authors.lastname: Reischl
authors.affiliation: Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, Regensburg, Germany.
authors.forename: André
authors.initials: A
authors.lastname: Gessner
authors.affiliation: Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, Regensburg, Germany. Electronic address: Jonathan.Jantsch@ukr.de.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Jantsch
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D016470:Bacteremia / Q000382:microbiology; D001769:Blood / Q000382:microbiology*; D000071997:Blood Culture; D015780:Carbapenems / Q000494:pharmacology*; D003091:Colistin / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D005260:Female; D006801:Humans; D007710:Klebsiella Infections / Q000382:microbiology; D041121:Klebsiella oxytoca / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D008565:Membrane Proteins / Q000235:genetics*; D016254:Mutagenesis, Insertional; D010957:Plasmids / Q000032:analysis; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems; D008565:Membrane Proteins; C425108:beta-lactamase bla(vim-2); D001618:beta-Lactamases; D003091:Colistin
keywords: Colistin resistance; Klebsiella oxytoca; Metallo-beta-lactamase; Multidrug-resistant