National surveillance study on carbapenem non-susceptible Klebsiella pneumoniae in Taiwan: the emergence and rapid dissemination of KPC-2 carbapenemase

PLoS One. 2013 Jul 24;8(7):e69428. doi: 10.1371/journal.pone.0069428. Print 2013.

Abstract

Objectives: The global spread and increasing incidence of carbapenem non-susceptible Klebsiella pneumoniae (CnSKP) has made its treatment difficult, increasing the mortality. To establish nationwide data on CnSKP spread and carbapenem-resistance mechanisms, we conducted a national surveillance study in Taiwanese hospitals.

Methods: We collected 100 and 247 CnSKP isolates in 2010 and 2012, respectively. The tests performed included antibiotic susceptibility tests; detection of carbapenemase, extended-spectrum β-lactamases (ESBL), and AmpC β-lactamases genes; outer membrane porin profiles; and genetic relationship with pulsed-field gel electrophoresis and multilocus sequence type.

Results: The resistance rate of CnSKP isolates to cefazolin, cefotaxime, cefoxitin, ceftazidime, and ciprofloxacin was over 90%. Susceptibility rate to tigecycline and colistin in 2010 was 91.0% and 83.0%, respectively; in 2012, it was 91.9% and 87.9%, respectively. In 2010, carbapenemase genes were detected in only 6.0% of isolates (4 bla IMP-8 and 2 bla VIM-1). In 2012, carbapenemase genes were detected in 22.3% of isolates (41 bla KPC-2, 7 bla VIM-1, 6 bla IMP-8, and 1 bla NDM-1). More than 95% of isolates exhibited either OmpK35 or OmpK36 porin loss or both. Impermeability due to porin mutation coupled with AmpC β-lactamases or ESBLs were major carbapenem-resistance mechanisms. Among 41 KPC-2-producing K. pneumoniae isolates, all were ST11 with 1 major pulsotype.

Conclusions: In 2010 and 2012, the major mechanisms of CnSKP in Taiwan were the concomitance of AmpC with OmpK35/36 loss. KPC-2-KP dissemination with the same ST11 were observed in 2012. The emergence and rapid spread of KPC-2-KP is becoming an endemic problem in Taiwan. The identification of NDM-1 K. pneumoniae case is alarming.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Carbapenems / pharmacology*
  • Cefazolin / pharmacology
  • Cefotaxime / pharmacology
  • Cefoxitin / pharmacology
  • Ceftazidime / pharmacology
  • Ciprofloxacin / pharmacology
  • Klebsiella pneumoniae / drug effects*
  • Klebsiella pneumoniae / enzymology*
  • Microbial Sensitivity Tests
  • Taiwan
  • beta-Lactamases / genetics
  • beta-Lactamases / metabolism*

Substances

  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Carbapenems
  • Ciprofloxacin
  • Cefoxitin
  • Ceftazidime
  • beta-Lactamases
  • carbapenemase
  • Cefazolin
  • Cefotaxime

Grant support

This study was supported by research grants from the Centers for Disease Control, Taiwan (DOH100-DC-1025 and DOH101-DC-1204). The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.