Dissemination of Klebsiella pneumoniae ST11 isolates with carbapenem resistance in integrated and emergency intensive care units in a Chinese tertiary hospital.

PURPOSE: The aim of the present study was to investigate the dissemination of carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates in integrated intensive care units (IICUs) and emergency ICUs (EICUs) for controlling the spread of CRKP in different ICUs of the hospital.

METHODOLOGY: From January 2016 to April 2017, a total of 46 non-duplicate CRKP isolates were consecutively isolated from a tertiary hospital. The production of carbapenemases was determined by the modified carbapenem inactivation method (mCIM) test. The resistance and virulence-associated genes were detected by PCR and DNA sequencing. A hypermucoviscosity phenotype was identified by the string test. Bacterial clonal relatedness of the CRKP isolates tested was determined by multi-locus sequence typing (MLST) and PFGE.

RESULTS

All CRKP isolates showed multiple drug resistance. All CRKP isolates harboured blaKPC-2-encoding carbapenemase and at least one of the other β-lactamase genes tested, with positive rates of 89.1  % (41/46) for blaCTX-M-65. qnrS was found among 76.1  % (35/46) of the CRKP isolates. A hypermucoviscosity phenotype was found in only two (4.3 %, 2/46) CRKP isolates. The virulence-associated genes with positive rates of more than 90  % among the 46 isolates tested included wabG (100 %, 46/46), ycf (100 %, 46/46), ureA (95.6 %, 44/46) and fim H (95.6 %, 44/46). MLST results showed that 46 CRKP isolates belonged to ST11 (95.6 %, 44/46) and ST86 (4.4 %, 2/46). PFGE patterns showed four clusters.

CONCLUSION

The CRKP ST11 clone with co-production of CTX-M-65 and KPC-2 disseminated in ICUs of this tertiary teaching hospital in central China. The emergence of CRKP with a hypermucoviscosity phenotype in ICUs should be of particular concern.