AUTHOR=Shao Chunhong , Jin Yan , Wang Wei , Jiang Meijie , Zhao Shuping 

TITLE=An Outbreak of Carbapenem-Resistant Klebsiella pneumoniae of K57 Capsular Serotype in an Emergency Intensive Care Unit of a Teaching Hospital in China

JOURNAL=Frontiers in Public Health

VOLUME=9

YEAR=2021

URL=https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2021.724212

DOI=10.3389/fpubh.2021.724212

ISSN=2296-2565

ABSTRACT=<p>The emergence of carbapenem-resistant hypervirulent <italic>K. pneumoniae</italic> (CR-hvKP) strains has increased the threat posed by <italic>K. pneumoniae</italic>. Here, we described an outbreak of 32 CR-hvKP isolates from the emergency intensive care unit (EICU) of a teaching hospital in China. Thirty-two CRKp isolates were collected from six patients and their surrounding environment in EICU. Antimicrobial susceptibility testing was performed using VITEK 2 compact system, E-test or the broth microdilution method. All isolates were serotyped, antimicrobial resistance genes and virulence-associated genes were screened using PCR. Multilocus sequence typing (MLST) and pulse-field gel electrophoresis (PFGE) were employed to characterize the genetic relationships among the CPKP isolates. The virulence capability of 11 CRKp isolates from six patients was evaluated through <italic>Galleria mellonella</italic> larva infection assay. PFGE showed that all 32 isolates belonged to one cluster, and MLST revealed that belonged to ST11. All isolates exhibited high resistance to β-lactam antibiotics, quinolones, and aminoglycosides. They were susceptible to ceftazidime/averbatan, tigecycline, and colistin. All 32 isolates harbored <italic>bla</italic><sub>KPC−2</sub>, <italic>bla</italic><sub>SHV−11</sub>, <italic>bla</italic><sub>TEM−1</sub>, <italic>rmtB</italic>, and <italic>qnrD</italic>. The serotype of all 32 isolates was K57. All 32 isolates contained 6 virulence genes, namely, <italic>fimH, iucB, mrkD, rmpA, uge</italic>, and <italic>wabG</italic>. Infection assays demonstrated high mortality in the <italic>Galleria mellonella</italic> model. Following measures implemented by the hospital, the outbreak was controlled. The mortality rate was 50.0%. The epidemiology of CR-hvKP should be monitored closely to detect early indications of this emerging public health threat.</p>