Mortality Associated with Bacteremia Caused by Carbapenem-Resistant Klebsiella pneumoniae: The Crucial Role of Therapy in Clinical Outcome.

This study analyzed factors associated with mortality in Klebsiella pneumoniae bacteremia, particularly the role of combination therapy. Medical records of 109 patients (2012-2018) were reviewed to assess risk factors for carbapenem-resistant K. pneumoniae (CRKP) bacteremia. The total 30-day mortality was 41.3%. Excess mortality was calculated for the following groups: multidrug-resistant (MDR) K. pneumoniae, CRKP, and carbapenem-susceptible K. pneumoniae. Of 109 isolates, 64.2% were CRKP. All patients received empirical therapy; 20.2% received monotherapy, while the remainder received combination therapy, which was linked to longer intensive care unit stays and higher primary bacteremia rates. Overall, inappropriate empirical treatment occurred in 62.4% of patients. Both monotherapy (40.9%) and combination therapy (36.8%) groups showed similarly high rates of inappropriate treatment. Hemodialysis catheter use was a risk factor (p = 0.0238). Third- and fourth-generation cephalosporins had the highest mortality (45.9%), whereas MDR strains showed the lowest (4.51%). Although combination therapy alone did not significantly reduce mortality, Kaplan-Meier analysis revealed no survival benefit. However, monotherapy increased mortality, suggesting that combination therapy may still play a role in mitigating outcomes. Carbapenem resistance in K. pneumoniae bacteremia remains alarmingly high and correlates with excess mortality and inappropriate empirical treatment.