Abstract
Background: To date, little is known about virulence characteristics of pyogenic liver abscess (PLA) causing multidrug resistant (MDR) Klebsiella pneumoniae (K. pneumoniae). It may be these strains are rare. The aim of this study was to analyze the virulence and molecular epidemiology of 12 MDR strains from 163 PLA cases in a tertiary teaching hospital from the perspective of clinical characteristics, virulence phenotypes and genotypes.Results: The virulence phenotypes of the twelve PLA-causing MDR K. pneumoniae were similar or even more obvious than those of sensitive hypervirulent Klebsiella pneumoniae control strains. These MDR strains were mainly non-K1/K2 serotypes and carried multiple virulence genes. Multilocus sequence typing (MLST) revealed the PLA-causing MDR strains had low clone correlation.Conclusions: This study was the first analysis on virulence factors of PLA-causing MDR strains. The virulent factors exhibited the coexistence of hypervirulence and multidrug resistance in PLA-causing MDR K. pneumoniae strains, and these MDR strains were mainly polyclonal spread and there was firstly found one ST11 carbapenem-resistant hypervirulent strain in PLA.