Prognostic factors of OXA-48 carbapenemase-producing Klebsiella pneumoniae infection in a tertiary-care Spanish hospital: A retrospective single-center cohort study.

OBJECTIVES:To describe the determinants of outcome of infections due to oxacillinase-48 (OXA-48) carbapenemase-producing Klebsiella pneumoniae (OXA-48-Kp). METHODS:A retrospective cohort study of 117 episodes of OXA-48-Kp infection were conducted. Multivariate Cox models identified factors predicting 14-day clinical response and 30-day all-cause mortality. RESULTS:A total of 77 (65.8%) isolates were susceptible to imipenem/meropenem. The 14-day clinical response and 30-day mortality rates were 41.9% and 28.2%. Catheter-related bloodstream infection (adjusted hazard ratio [aHR]: 8.33; 95% confidence interval [95%CI]: 3.19-21.72; P-value <0.001), urinary tract infection (aHR: 3.04; 95%CI: 1.39-6.66; P-value = 0.006) and early appropriate treatment (aHR: 1.77; 95%CI: 0.97-3.22; P-value = 0.064) predicted clinical response, whereas severe sepsis had a deleterious impact (aHR: 0.22; 95%CI: 0.10-0.50; P-value <0.001). Lower respiratory tract infection (aHR: 6.58; 95%CI: 2.83-15.29; P-value <0.001) and bloodstream infection (aHR: 2.33; 95%CI: 1.05-5.15; P-value = 0.037) were associated with 30-day mortality, whereas definitive therapy including ≥1 active agent (aHR: 0.26; 95%CI: 0.11-0.63; P-value = 0.003) and source control (aHR: 0.35; 95%CI: 0.14-0.91; P-value = 0.030) were protective. Combination therapy did not seem to be associated with better outcomes. CONCLUSIONS:Appropriate antimicrobial treatment was protective for 30-day mortality in OXA-48-Kp infections. Carbapenems are usually active, whereas combination therapy appeared not to confer additional benefit.