Clinical Characteristics and Risk Factors for Fatality in Patients with Bloodstream Infections Caused by Glucose Non-fermenting Gram-negative Bacilli

Abstract

Glucose non-fermenting Gram-negative bacilli (GNF-GNB) bloodstream infections (BSIs) are often hospital-acquired and are important causes of morbidity and mortality. Our objectives were to evaluate the epidemiology and clinical characteristics of GNF-GNB BSIs, and to identify risk factors for fatality. We retrospectively reviewed cases of GNF-GNB BSIs in adult patient (≥ 18 years of age) hospitalized between January and December 2005. A total 221 GNF-GNB bacteremic episodes (200 hospital-acquired and 21 community-acquired) in 215 patients (123 men and 92 women; mean age, 63.38±16.10 years) were included in our study. Of these, 52.5% were elderly (age > 65). Malignancy (43.0%), diabetes mellitus (22.6%) and steroid use (22.6%) were the major underlying diseases/conditions. Central venous catheter (CVC) placement had been carried out in 57.5% of patients. The 28-day mortality was significantly higher in those patients with: liver cirrhosis, steroid use, pneumonia as the primary source of infection, intensive care unit-acquired infections, septic shock, and a high Pitt bacteremia score (≥ 4 points). Liver cirrhosis [odds ratio (OR)=6.4; 95% confidence interval (CI)=1.7-23.9; p < 0.01)], hematologic malignancy (OR=3.9; 95% CI=1.1-14.1; p=0.04), pneumonia (OR=4.0; 95% CI=1.4 - 11.0; p< 0.01), septic shock (OR=13.0; 95% CI=4.6-36.6; p< 0.01), and intensive care unit-acquired infections (OR=2.9; 95% CI=1.1-8.0; p= 0.04) were all independent risk factors for fatality. Our data suggested that CVC placement and steroid use predispose to GNF-GNB bacteremia. Early removal of CVC and avoidance of steroids may minimize the chances of acquiring this infection, which is of particular importance for patients at high risk of mortality once they are infected with GNF-GNB.