A Retrospective Analysis of Risk Factors and Outcomes of Carbapenem-Resistant Klebsiella pneumoniae Bacteremia in Nontransplant Patients.

Background: Carbapenem-resistant Klebsiella pneumoniae (CRKP) has become a major problem among nosocomial infections, and it is a serious threat to patients. The clinical characteristics and outcome of CRKP bloodstream infection (BSI) in nontransplant patients remains unelucidated. The aim of this study was as follows: identify the risk factors of CRKP infection; generate new ideas for prevention; and generate new ideas for the most effective therapeutic management in nontransplant patients.

Methods: The study retrospectively analyzed the clinical and microbiological data of nontransplant patients with K pneumoniae (KP) bacteremia from January 2013 to December 2015 to identify risk factors, clinical features, and outcomes using multivariate logistic regression analysis.

Results: Of the 371 patients with KP-BSI in nontransplant patients included in this study, 28.0% (N = 104) had CRKP. The 28-day mortality was higher in patients infected with CRKP (55.8%) than in those with carbapenem-susceptible KP (13.9%) (P < .001). Multivariate analysis showed previous gastric catheterization, previous use of carbapenems, hypoproteinemia, and high Acute Physiologic Assessment and Chronic Health Evaluation II scores as independent risk factors for CRKP-BSIs. Carbapenem-resistant KP infection, severe illness, and tigecycline therapy were independent risk factors for death from KP-BSIs. Taken together, inappropriate antibiotic treatment both in empirical and definitive therapy and imipenem minimum inhibitory concentrations (MICs) of >8 mg/L were associated with poor clinical outcome.

Conclusions: Nontransplant patients with CRKP-BSI had higher mortality. Carbapenems exposure was an independent risk factor for CRKP infection. Imipenem MICs of >8 mg/L, tigecycline therapy, and inappropriate treatments increased the 28-day mortality of KP-BSI patients.