Nosocomial bloodstream infections in a newborn intensive care unit: a case-matched control study of morbidity, mortality and risk.

Routine surveillance of 1252 newborns admitted over a four-year period to a newborn intensive care unit (ICU) identified 49 (4%) with nosocomial bloodstream infections. Forty-nine control subjects without such infections were selected, matching for birth weight, gestational age, and at least three diagnoses per patient. Overall, 27% of cases and 6% of controls died (p = 0.01) and significant differences persisted when cases with multiple bloodstream infections were removed from analysis. Although small numbers of case-control pairs remained for analysis, significant differences disappeared when cases with multiple bloodstream infections plus case-control pairs discordant for presence/absence of nosocomial infections at other sites were eliminated from comparison. On the average, all cases and controls were hospitalized for 70 +/- 14 days and 50 +/- 8 days, respectively, but when cases with multiple bloodstream infections or the multiple bloodstream infections-discordant pair group were removed from analysis, the significant difference in hospitalization disappeared. A strong association between nosocomial infections at sites other than the bloodstream and bloodstream infections was demonstrated and may suggest a means of reducing the incidence of bloodstream infections in a high risk population.