Prevalence of nosocomial infections in Italy: result from the Lombardy survey in 2000.

A one-day survey was carried out in 88 out of 113 public hospitals in Lombardy to obtain prevalence rates of hospital-acquired infections (HAIs) by hospital departments and to identify the pathogens more frequently involved. In total 18667 patients were surveyed, representing 72% of the average daily total of occupied beds in public hospitals in Lombardy. The overall prevalence of HAI was 4.9%. The highest prevalence was observed in intensive care units and in spinal units. The prevalence of bloodstream infections was 0.6%; pneumonia 1.1%; urinary tract infections 1.6% and gastrointestinal infections 0.4%. In surgical patients the prevalence of surgical site infections was 2.7%. The most frequently isolated pathogen from all sites of infections was Escherichia coli (16.8%), followed by Staphylococcus aureus (15.0%), Pseudomonas aeruginosa (13.2%) and Candida spp. (8.7%). Methicillin-resistant S. aureus accounted for 23% of all isolated S. aureus. The results provide baseline data for rational priorities in allocation of resources, for further studies and for infection control activities.