Factores de riesgo de mortalidad en pacientes con bacteriemia por cepas productoras de betalactamasas de espectro extendido

Abstract

Objective To identify risk factors for mortality in patients with bloodstream infection by extended-spectrum beta-lactamase (ESBL)-producing microorganisms. Material and methods A retrospective study in patients with bloodstream infection by ESBL-producing microorganisms from January 2000 to December 2006 was carried out. Results A total of 4,172 bloodstream infections were identified, 1,218 (29.2%) and 226 (5.4%) of which were caused by Escherichia coli and Klebsiella pneumoniae, respectively. The overall mortality rate was 50.9% in patients with bacteriema due to ESBL-producing strains. The binomial logistic regression model, adjusted for age and severity, identified admission to an intensive care unit (OR 38,631; 95%CI:3,375-424,618; P = .002) and a SAPS II severity index score >30 in the 24-48 h before obtaining blood culture (OR 17,980; 95% CI:2,193-170,439; P = .010) as factors associated to mortality, while the urinary tract as primary site of infection was an independent determinant for non-mortality (OR 0.184; 95% CI:0.034-0.975; P = .047). Conclusions Patients with suspicion of bacteriema who have been admitted to the ICU with a score of elevated severity should be candidates for early empirical treatments as they have a greater risk of mortality. However, the benefit of this strategy may be limited due to the baseline severity of the patient.