title: Virulence and plasmid transferability of KPC Klebsiella pneumoniae at the Veterans Affairs Healthcare System of New Jersey.
abstract: Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae infections are associated with high mortality; however, little is known about the virulence determinants of KPC-producing K. pneumoniae. At the Veterans Affairs New Jersey Healthcare System (VA NJHCS), we investigated the virulence and plasmid transferability of 60 clinically unique KPC-containing K. pneumoniae isolates. All 60 isolates were negative for known virulence factors K1, K2, and K5 capsular antigens; rmpA; and the aerobactin gene by polymerase chain reaction. Isolates varied in their susceptibility to neutrophil phagocytosis, but were less resistant than the virulent serotype K1 isolate. Additionally, no deaths were seen on murine lethality studies. Conjugation results of this study showed that the bla(KPC) gene can be transferred into an Escherichia coli J-53 strain but not to E. coli JP-995. However, the stability is very limited as E. coli J-53 does not retain bla(KPC)-containing plasmids for any period of time. The lack of virulence factors in the set of KPC-producing K. pneumoniae studied suggests that morbidity and mortality may be due to detection issues or lack of effective antibiotics.
authors.affiliation: Division of Infectious Diseases, National Health Research Institutes, Zhunan, Taiwan.
authors.forename: L Kristopher
authors.initials: LK
authors.lastname: Siu
authors.forename: Jung-Chung
authors.initials: JC
authors.lastname: Lin
authors.forename: Eric
authors.initials: E
authors.lastname: Gomez
authors.forename: Robert
authors.initials: R
authors.lastname: Eng
authors.forename: Tom
authors.initials: T
authors.lastname: Chiang
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000942:Antigens, Bacterial / Q000235:genetics; D000954:Antigens, Surface / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics*; D015780:Carbapenems / Q000494:pharmacology; D004926:Escherichia coli / Q000235:genetics*; D022761:Gene Transfer, Horizontal; D006801:Humans; D007711:Klebsiella pneumoniae / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity*; D051379:Mice; D008826:Microbial Sensitivity Tests; D009504:Neutrophils / Q000502:physiology; D009515:New Jersey; D010587:Phagocytosis; D010957:Plasmids; D016133:Polymerase Chain Reaction; D013045:Species Specificity; D014728:Veterans; D014774:Virulence / Q000235:genetics; D037521:Virulence Factors / Q000235:genetics; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D000942:Antigens, Bacterial; D000954:Antigens, Surface; D001426:Bacterial Proteins; D015780:Carbapenems; C030659:K antigens; D037521:Virulence Factors; D001618:beta-Lactamases; C063912:carbapenemase