Are the "good old" antibiotics still appropriate for early-onset neonatal sepsis? A 10 year survey.

Background: Early-onset neonatal sepsis is a major cause of morbidity and mortality among newborn infants. Objectives: To determine the incidence, type of pathogens and resistance to antibiotics among newborns with early-onset neonatal sepsis, and to identify the risk factors predisposing infants to resistant pathogens in order to reevaluate antibiotic regimens appropriate for resistant bacteria in these high risk neonates. Methods: We retrospectively studied maternal and neonatal variables of 73 term and near-term infants and 30 preterm infants, born over a period of 10.5 years and exhibiting early-onset neonatal sepsis (positive blood cultures in the first 72 hours of life). Results: Predominant pathogens in term and near-term infants were gram-positive compared with gram-negative organisms (mostly Escherichia coli) in preterm infants. Mothers of infants with antibiotic-resistant organisms were more likely to have prolonged rupture of membranes and prolonged hospitalization before delivery and to be treated with antibiotics. No trends towards more resistant strains of pathogens were recorded over the 10.5 years of the study period. Conclusions: Early-onset neonatal sepsis in term infants differs in bacterial species from that in preterm infants, with predominantly gram-positive organisms in term and near-term infants and gram-negative organisms in preterms. Rates of bacterial resistance to the combination of ampicillin and gentamicin, though higher among infants born to mothers with prolonged hospitalization who had been treated with antibiotics, still remained very low in our department. Thus, it seems that our classic antibiotic regimen is still appropriate for both term and preterm newborns.