Clinical and Molecular Analysis of ST11-K47 Carbapenem-Resistant Hypervirulent Klebsiella pneumoniae: A Strain Causing Liver Abscess

Klebsiella pneumoniae has been the predominant pathogen of liver abscess, but ST11-K47 carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKP) has rarely been studied as the causative organism. We identified an ST11-K47 CR-hvKP (HvKp-su1) from the drainage fluid of a liver abscess in a Chinese man who was diagnosed with liver abscess combined with diabetes, pneumonia, pleural infection, abdominal abscess, and splenic abscess. HvKp-su1 was non-hypermucoviscous and lacked the magA and rmpA genes and pLVPK plasmid but exhibited high virulence, with a high mortality rate (90%) to wax moth larvae (G. mellonella), similar to the hypervirulent Klebsiella pneumoniae ATCC43816 (91.67%). Whole-genome sequencing and bioinformatics analysis indicated that HvKp-su1 possesses a plasmid similar to a type of pLVPK-like plasmid (JX-CR-hvKP-2-P2), which is an uncommon plasmid in CR-hvKP. HvKp-su1 carried multiple resistance genes, including bla(KPC-2). bla(TEM-1), bla(SHV-55), and bla(CTX-65); hypervirulence genes such as aerobactin (iutA), salmochelin (iroEN), and yersiniabactin (ybtAEPOSTLIX); and the type 3 fimbriae-encoding system (mrkACDF). Moreover, v_5377 and v_5429 (cofT, CFA/III (CS8)) located on plasmid 1 were simultaneously predicted to be virulence genes. After the long-term combination use of antibiotics, the patient successfully recovered. In summary, our study clarified the clinical and molecular characteristics of a rare ST11-K47 CR-hvKP (HvKp-su1), raising great concerns about the emergence of ST11-K47 CR-hvKP with multidrug resistance and hypervirulence, and providing insights into the control and treatment of liver abscess caused by ST11-K47 CR-hvKP.