[Prevalence of nosocomial infections in Intensive Care Units in Triveneto area, Italy]

Nosocomial infection is one of the most common complications affecting patients admitted in intensive care units (ICU). The aim of this study is to evaluate rates of ICU-acquired infections, potential risk factors for these infections, causative microorganisms and antibiotic resistance patterns.

A 1-day point-prevalence study was conducted in 39 ICUs in Triveneto area (Italy) in November 1998. The overall study population included 188 patients with mean age of 61.4+/-19.3 years; the mean SAPS II score at entry into the ICU was 44.4+/-16.8 and the median duration of hospitalization was 9 days (range 2-636).

A total of 59 patients (31.4%) had 79 episodes of ICU-acquired infections; pneumonia (45.5%), bloodstream infection (30.4%), and urinary tract infection (11.4%) were the most frequent types of infection. The leading causative microorganisms were S. aureus (24.4%, 77% of them were resistant to methicillin), Enterobacteriaceae (24.4%), P. aeruginosa (23.2%), fungi (12.2%), coagulase-negative staphylococci (7.3%) and Enterococcus spp (4.9%). Independent risk factors for nosocomial infections were duration of hospitalization >7 days (OR 4.29, 95% CI 1.82-10.1), SAPS II score >30 (OR 3.34, 95% CI 1.0-11.18), total parenteral nutrition (OR 2.69, 95% CI 1.19-6.07) and tracheostomy (OR 1.88, 95% CI 0.84-4.20).

Nosocomial infections are relatively frequent in Triveneto area ICUs. The predominance of pneumonia and bloodstream infection, and the high frequency of antibiotic-resistant pathogens indicate that resources had to be assigned towards the implementation of control programs of those infections, monitoring of antibiotic resistance and prescription, and antibiotic therapy guidelines.