Prolonged Duration of Initial Empirical Antibiotic Treatment Is Associated With Increased Rates of Necrotizing Enterocolitis and Death for Extremely Low Birth Weight Infants

Our objectives were to identify factors associated with the duration of the first antibiotic course initiated in the first 3 postnatal days and to assess associations between the duration of the initial antibiotic course and subsequent necrotizing enterocolitis or death in extremely low birth weight infants with sterile initial postnatal culture results.

We conducted a retrospective cohort analysis of extremely low birth weight infants admitted to tertiary centers in 1998-2001. We defined initial empirical antibiotic treatment duration as continuous days of antibiotic therapy started in the first 3 postnatal days with sterile culture results. We used descriptive statistics to characterize center practice, bivariate analyses to identify factors associated with prolonged empirical antibiotic therapy (> or =5 days), and multivariate analyses to evaluate associations between therapy duration, prolonged empirical therapy, and subsequent necrotizing enterocolitis or death.