Comparison of beta-lactam monotherapy and combination with fluoroquinolone therapy as initial empiric treatment in patients with hospital-acquired pneumonia: A Korean multicenter cohort study

초록

Introduction There is insufficient data on the effect of empiric combination therapy for Pseudomonas aeruginosa inpatients with hospital-acquired pneumonia (HAP). We aimed to investigate whether empiric combination therapy was associated with decreased mortality in patients with HAP. Methods This was a multicenter retrospective cohort study of patients admitted to 16 tertiary or general hospitals in Korea from January 1 to December 31, 2019. The patients were divided into two groups according to mono or combination empiric antibiotic therapy for Pseudomonas aeruginosa. Propensity score matching (PSM) was used to reduce bias between groups. The primary outcome was 30-day mortality. Results During the study period, 1193 adult patients with HAP were enrolled. Beta-lactam monotherapy was 56.9%(n=429), and combination therapy with fluoroquinolones was 43.1% (n=325). Gram-negative pathogens were 29.6%,with 11.1% of Acinetobacter baumannii and 7.0% of Pseudomonas aeruginosa. Multidrug resistant (MDR) pathogens were 26.9%, and the MDR rates of Acinetobacter baumanniiand Pseudomonas aeruginosa were 90% (76/84) and 83%(44/53), respectively. After 1:1 PSM, a matched cohort with 568 patients was generated. There was no significant difference in the 30-day mortality rate between two groups(16.8% vs. 17.2%,p=0.871), even after PSM (16.5% vs. 49 17.3%, p=0.823). Conclusions In Korea, the most common gram-negative bacterial pathogens of HAP were Acinetobacter baumanniiand Pseudomonas aeruginosa, and the MDR rates of both organisms are high. Empiric antipseudomonal beta-lactam combined with fluoroquinolone showed no survival benefit in patients with HAP. Further nationwide study regarding antibiotic susceptibility data on nosocomial Pseudomonasaeruginosa is needed.