Epidemiologic trends in nosocomial bacteremia in a neonatal intensive care unit.

The primary goal of this study was to analyze the epidemiologic features of nosocomial bloodstream infection (NBSI) in a neonatal intensive care unit over a 7-year period. All neonatal patients with NBSI treated from January 1997 to December 2003 were retrospectively analyzed. 232 NBSI episodes were diagnosed in 208 patients. The average NBSI patient-day rates were 4.69 and 2.59 per 1000 patient-days in 1997-1999 and 2000-2003, respectively. The average NBSI rates were 5.00 and 1.50 per 1000 patient days in neonates <1500 g and > or =1500 g, respectively. The proportion of Gram-positive organisms increased from 24% in 1997-2001 to 41% in 2002-2003, whereas the proportion of Gram-negative isolates decreased from 65% in 1997-2001 to 47% in 2002-2003. The implementation of measures for the prevention of nosocomial infection was associated with the reduction of NBSI rates. Low birth weight was demonstrated to be a significant risk factor for NBSI. The fact that Gram-positive organisms were isolated in increasing frequency may impact on the appropriate selection of empiric antimicrobial therapy for NBSI in the neonatal intensive care unit.