Antimicrobial resistance and virulence factors of Klebsiella pneumoniae affecting 30 day mortality in patients with bloodstream infection

• Published in: Journal of antimicrobial chemotherapy Vol. 74; no. 1; pp. 190 - 199
• Main Authors: Kim, Dokyun, Park, Byeol Yi, Choi, Min Hyuk, Yoon, Eun-Jeong, Lee, Hyukmin, Lee, Kwang Jun, Park, Yoon Soo, Shin, Jong Hee, Uh, Young, Shin, Kyeong Seob, Shin, Jeong Hwan, Kim, Young Ah, Jeong, Seok Hoon
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 01.01.2019
• Subjects: Aged; Aged, 80 and over; Drug Resistance, Bacterial; Female; Humans; Klebsiella Infections - microbiology; Klebsiella Infections - mortality; Klebsiella pneumoniae - drug effects; Klebsiella pneumoniae - isolation & purification; Klebsiella pneumoniae - pathogenicity; Male; Middle Aged; Prospective Studies; Risk Factors; Sepsis - microbiology; Sepsis - mortality; Survival Analysis; Virulence Factors - analysis
• ISSN: 0305-7453; 1460-2091
• DOI: 10.1093/jac/dky397

Abstract Objectives To investigate the risk factors of patients with Klebsiella pneumoniae (KP) bloodstream infection (BSI) with a focus on antimicrobial resistance and virulence factors. Methods All KP BSI patients (n = 579) from six general hospitals during a 1 year period were included in this study. The risk factors of hosts and causative KP isolates were assessed to determine associations with the 30 day mortality of KP BSI patients by multivariate Cox hazards modelling. Results The 30 day mortality rate of KP BSI patients was 16.9% (98/579). Among the host-associated factors, increased SOFA score and leucopenia status exhibited strong associations with increased 30 day mortality. Among the pathogenic factors, carriage of the pks gene cluster (adjusted HR 1.80; 95% CI 1.16–2.79) was a risk factor, especially when accompanied by MDR. In this regard, KP isolates of the wzi50 capsular type (n = 22) frequently harboured pks (63.6%, 14/22) and ybtA (68.2%, n = 15) and mostly exhibited MDR (63.6%, n = 14), resulting in increased 30 day mortality. In contrast, hypermucoviscous KP isolates showed an inverse association with 30 day mortality (adjusted HR 0.55; 95% CI 0.33–0.90). Conclusions Despite the reported virulence of hypermucoviscous KP strains, they were associated with good prognoses in KP BSI patients. Importantly, carriage of the pks gene cluster, which is responsible for the synthesis of colibactin, was a relevant marker of early mortality.