Indexed on: 10 Jun '18Published on: 10 Jun '18Published in: Journal of Global Antimicrobial Resistance
Hypermucoviscous Klebsiella pneumoniae (HMKP) has been increasingly recovered in clinical isolates. This study sought to examine the microbiological and epidemiologic characteristics of HMKP strains in a tertiary hospital at Hangzhou in China. HMKP isolates were collected and identified via matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF). A string test was performed for the hypermucoviscous phenotype. Antimicrobial susceptibility to antibiotic agents was determined. Multilocus sequence typing, capsular serotypes and virulence-associated genes of HMKP isolates were assessed. Forty-two HMKP strains with positive string tests were collected. Thirty-two (76.2%) HMKP isolates were carbapenem-susceptible (CS-HMKP) and ten (23.8%) HMKP isolates were carbapenem-resistant (CR-HMKP). CS-HMKP strains were more susceptible to antibiotics than CR-HMKP strains. K1 (50%) and K2 (12.5%) were the main capsular serotypes of all HMKP isolates. K57 was first reported in the CR-HMKP strain. ST163 was the main sequence type (50%) of CS-HMKP strains, while ST11 was a unique sequence type of CR-HMKP strains. The regulator of the mucoid phenotype gene rmpA and other virulence factors (allS, kfu, iutA, entB, iroN, fimH and wabG) were present in more than 80% of the HMKP strains. Patients with CR-HMKP strains had a higher mortality rate than those with CS-HMKP strains. K1 and K2 were the main capsular serotypes of these HMKP strains. The emergence of carbapenem-resistant HMKP should be a concern, as it had an increased mortality rate, especially with ST11 CR-HMKP strains, demonstrating the global epidemic of carbapenem resistance. Copyright © 2018. Published by Elsevier Ltd.