title: Clinical and molecular characteristics of multi-clone carbapenem-resistant hypervirulent (hypermucoviscous) Klebsiella pneumoniae isolates in a tertiary hospital in Beijing, China.
abstract: OBJECTIVE
  To provide the clinical and molecular characteristics of carbapenem-resistant hypervirulent (hypermucoviscous) Klebsiella pneumoniae (cr-hvKP) in a tertiary hospital in Beijing, China.
  
  
  METHODS
  The clinical characteristics of four patients with cr-hvKP isolates and 29 patients with carbapenem-resistant classic K. pneumoniae (cr-cKP) infections were analyzed retrospectively. The molecular characteristics of cr-hvKP and cr-cKP isolates were compared.
  
  
  RESULTS
  The KPC-2 gene was detected in all cr-hvKPs except for cr-hvKP6. The cr-hvKPs belonged to three sequence types (STs; ST25, ST65, and ST11), with three pulsed-field gel electrophoresis patterns (I, II, and III) and two capsular serotypes (K2 and non-typeable). Although cr-hvKP1-7 did not cause invasive clinical syndromes such as community-acquired liver abscess with or without extrahepatic complications, they were all nosocomially acquired; cr-hvKP1-5 were clones disseminated between patients A and B. Compared with cr-cKPs, pLVPK-related loci, repA, iroN, and K2 capsular serotype were more prevalent in cr-hvKPs, although no significant difference was found in clinical characteristics between patients with cr-hvKP and cr-cKP infection.
  
  
  CONCLUSIONS
  The hypervirulent ST65 and ST25K. pneumoniae, along with carbapenem-resistant clonal populations ST11, appear to have evolved into cr-hvKP strains. The evidence of bi-directional evolution and emergence of hospital-acquired multi-clone cr-hvKP indicates a confluence of virulence and carbapenem resistance, which might pose major problems in the management of K. pneumoniae infection.
authors.affiliation: Department of Laboratory Medicine, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing, 100191, China.
authors.forename: Bei
authors.initials: B
authors.lastname: Yao
authors.affiliation: Department of Laboratory Medicine, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing, 100191, China.
authors.forename: Xiumei
authors.initials: X
authors.lastname: Xiao
authors.affiliation: Department of Respiratory Medicine, Peking University Third Hospital, Haidian District, Beijing, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Wang
authors.affiliation: Department of Laboratory Medicine, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing, 100191, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Department of Laboratory Medicine, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing, 100191, China.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Laboratory Medicine, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing, 100191, China. Electronic address: zhangjiebjmu15@163.com.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000068476:Beijing; D015780:Carbapenems / Q000494:pharmacology*; D002681:China; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D006801:Humans; D007710:Klebsiella Infections / Q000175:diagnosis / Q000382:microbiology*; D007711:Klebsiella pneumoniae / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D008297:Male; D012189:Retrospective Studies; D062606:Tertiary Care Centers; D014774:Virulence / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems
keywords: Carbapenem-resistant; Hypermucoviscous; Hypervirulent; Klebsiella pneumoniae