Clinical characteristics and outcome of elderly patients with community-onset bacteremia.

Objectives: To evaluate characteristics and prognostic factors of community-onset bloodstream infection (Co-BSI) in elderly patients (≥65 years).

Methods: Analysis of a prospective series of Co-BSI at a tertiary hospital (2005-2011). Predictors of 30-day mortality were established by logistic regression analysis.

Results: A total of 2605 episodes of Co-BSI were identified and empirical antibiotic treatment was inappropriate in 404 (15.5%). Thirty-day mortality was 11.4% and was independently associated with age (75-84 years OR 1.9, 1.37-2.67; ≥85 OR 2.85, 1.93-4.21), previous hospitalization (OR 1.45, 1.05-2.00), a fatal underlying disease (OR 2.81, 2.10-3.76), neutropenia (OR 2.62, 1.54-4.43), absence of fever (OR 1.99, 1.26-3.12), shock (OR 7.96, 5.83-10.89), inappropriate empirical treatment (OR 1.49, 1.03-2.16), isolation of Staphylococcus aureus (methicillin-resistant OR 2.83, 1.38-5.78; methicillin-susceptible OR 3.24, 1.98-5.32), enterococci (OR 2.02, 1.14-3.59) or Enterobacteriaceae resistant to third-generation cephalosporin (3GCR-E) (OR 1.96, 1.16-3.32) and having endovascular non-catheter (OR 4.64, 2.51-8.59), abdominal (OR 3.65, 2.12-6.27), skin/soft tissue (OR 3.48, 1.90-6.37), respiratory (OR 2.80, 1.75-4.50) or unknown (OR 1.83, 1.17-2.87) source.

Conclusions: Age is a prognostic factor and appropriateness of empirical treatment is the only modifiable variable. S. aureus, enterococci and 3GCR-E may be the microorganisms with major prognostic significance; hence efforts should be made to improve their management.