Epidemiological, clinical, and microbiological characteristics of late-onset sepsis among very low birth weight infants in Israel: A national survey

Objective. Nosocomial infections are a serious problem among very low birth weight (VLBW) infants. We studied the association between late-onset sepsis (LOS) and mortality and morbidity in VLBW infants. Methods. From a national cohort of 5555 VLBW infants born in Israel during 1995 through 1998, 4829 survived at least 3 days and composed the study population. Maternal, perinatal, or postnatal variables that showed a significant association with LOS in a univariate analysis were tested in a bivariate analysis (adjusted for gestational age). Variables with P less than or equal to .1 were then tested by a multiple logistic regression for assessing the net effect of each variable on the risk for LOS. Results. One or more episodes of bloodstream-proven LOS occurred in 1453 infants (30%). Gram-positive and Gram-negative bacteria accounted for 55.4% and 31.2% of microbes, respectively, mainly coagulase-negative Staphylococci and Klebsiella. Compared with those without LOS, infants with LOS had a significantly higher mortality rate (16.9% vs 8.6%). Mortality after Gram-negative LOS (26.2%) and Candida LOS (27.6%) was similar and significantly higher than with Gram-positive LOS (8.7%). Significant independent predictors of LOS were decreasing gestational age, cesarean section, mechanical ventilation, patent ductus arteriosus, necrotizing enterocolitis, and bronchopulmonary dysplasia. Conclusions. LOS occurred in 30% of Israeli VLBW infants. Six strong independent predictors for LOS were identified. Recognition and awareness of the epidemiologic, clinical, and microbiologic characteristics of LOS remain the keystones for management of this nosocomial infection.