[Enterococcal infections in critically ill patients admitted to ICU]

To determine the frequency of infections caused by Enterococcus spp. in critically ill patients admitted to ICUs in Spain and to describe the clinical features and outcome of those patients in whom this pathogen was isolated.

Prospective, observational, multicenter study. Patients admitted to the ICUs who participated in the National Surveillance Study of Nosocomial Infections (ENVIN) from 1997 to 2001 were included. Patients were classified as infected by Enterococcus spp., infected by other pathogens, and without nosocomial infection (non-infected).

Of 21,972 patients, 2,177 (9.9%) had acquired 3,490 nosocomial infections during their stay in the ICU. In 223 patients (10.2%), 239 episodes of infections in which one of the causative pathogen was Enterococcus spp. were identified (cumulative incidence 1.1 episodes of Enterococcus spp. infection per 100 patients). Enterococcus spp. accounted for urinary infection in 14.3% of cases and secondary bacteremia in 12.2% especially those related with abdominal infection (20%) and soft tissue infection (21.4%). Predominant species was E. faecalis in 197 isolates (82.4%). After multivariate analysis, variables significantly associated with infection caused by Enterococcus spp. included: age (odds ratio [OR]=1.13; 95% confidence interval [CI], 1.01-1.25); APACHE II score (OR=1.19; CI 95%, 1.07-1.32); and length of ICU stay (OR=1.02; CI 95%, 1.01-1.03). There were no differences in the overall ICU mortality rate between patients with Enterococcus spp. infection (31.8%) and those with infection caused by other pathogens (31.8%), although in both cases the mortality rate was significantly higher than in non-infected patients (11.1%).

Enterococcus spp. was present in 10.2% patients with ICU-acquired infection. Infection by Enterococcus spp. mainly occurred in the form of urinary tract infection and secondary bacteremia, mainly related to abdominal and soft tissue infections. E. faecalis predominated in all foci. There were no differences in mortality between patients with Enterococcus spp. infection and patients with infection caused by other pathogens.