Clinical and Microbiological Characteristics of Bacteremic Pneumonia Caused by Klebsiella pneumoniae

Abstract

<i>Klebsiella pneumoniae</i> is a common pathogen of nosocomial pneumonia worldwide and community-acquired pneumonia (CAP) in Asia. Previous studies have shown that <i>K. pneumoniae</i> bacteremic CAP is associated with high mortality. We aimed to revisit <i>K. pneumoniae</i> bacteremic pneumonia in the current era and determine the risk factors associated with 28-day mortality. Between January 2014 and August 2020, adult patients with <i>K. pneumoniae</i> bacteremic pneumonia in a medical center in Taiwan were identified. Clinical and microbiological characteristics were compared between CAP and nosocomial pneumonia. Risk factors for 28-day mortality were analyzed using multivariate logistic regression. Among 150 patients with <i>K. pneumoniae</i> bacteremic pneumonia, 52 had CAP and 98 had nosocomial pneumonia. The 28-day mortality was 52% for all patients, 36.5% for CAP, and 60.2% for nosocomial pneumonia. Hypervirulent <i>K. pneumoniae</i> was more prevalent in CAP (61.5%) than in nosocomial pneumonia (16.3%). Carbapenem-resistant <i>K. pneumoniae</i> was more prevalent in nosocomial pneumonia (58.2%) than in CAP (5.8%). Nosocomial pneumonia, a higher Severe Organ Failure Assessment score, and not receiving appropriate definitive therapy were independent risk factors for 28-day mortality. In conclusion, revisiting <i>K. pneumoniae</i> bacteremic pneumonia in the current era showed a high mortality rate. Host factors, disease severity, and timely effective therapy affect the treatment outcomes of these patients.