Bloodstream infections due to Escherichia coli and Klebsiellaspp. producing extended-spectrum lactamase: factors influencing adequacy and mortality

Abstract number: P1319

Peralta G., Anibarro L., Lamelo M., Velasco M., Delgado-Iribarren A., Horcajada J.P., Montero M., Fariñas M.C., Alonso J., Roiz M., Capdevila J.A.

Objectives: Bloodstream infections due to E. coli and Klebsiella producing extended-spectrum b-lactamase (ESBL) are increasing. The precise role of factors influencing adequacy of empirical antibiotic treatment and outcome are controversial.

Methods: Retrospective study of cases Escherichia coli and Klebsiella spp ESBL bacteremia from 2003 to 2008, in 18 Hospitals of Spain. Cases were identified from Microbiology laboratory databases. Empirical antimicrobial therapy was judged to be either adequate or inadequate on the basis of the in vitro susceptibility of an isolated organism, and/or the initiation of antibiotic treatment within 24 h of blood culture extraction. ESBL production was screened by the double disc synergy method as a complementary test for automated systems.

Results: In the period of study 372 cases of bacteremia (85% E. coli) with a mortality of 24.3% were identified. The origin of bacteremia were mostly urinary (50.7%), biliary (10.8%), and of unknown origin (10%). Of them 144 (38.8%) cases were nosocomial and 127 (34.4%) health related. Empirical antibiotic treatment was adequate in 45% of cases. In a logistic regression analysis the only clinical factor associated with the adequacy of empirical antibiotic therapy was the abdominal origin (ORa: 3.19; 95% CI: 1.26–8.11). Factors associated with mortality in the whole cohort were severe sepsis or shock (ORa: 8.84, 95% CI: 4.76–16.41), Charlson index score >2 (ORa: 2.92; 95% CI: 1.51–5.64), nosocomial acquisition (ORa: 2.26; 95% CI: 1.19–4.28) and adequate empirical treatment (ORa: 0.35; 95% CI: 0.21–0.94).

Conclusions: Mortality of E. coli and Klebsiella spp. ESBL bloodstream infections is high. Adequacy of empirical antibiotic treatment is an independent risk factor for mortality in these patients.

Session Details

Date: 10/04/2010
Time: 00:00-00:00
Session name: Abstracts 20th European Congress of Clinical Microbiology and Infectious Diseases
Location: Vienna, Austria, 10 - 13 April 2010
Presentation type:
Back to top