Ampicillin versus penicillin in the empiric therapy of extremely low-birthweight neonates at risk of early onset sepsis.

BACKGROUND

There are no comparative data on the impact of different empiric antibiotic regimens on early bowel colonization as well as on clinical efficacy in extremely low-birthweight (ELBW) neonates at risk of early onset sepsis (EOS).

METHODS

A subgroup analysis was carried out of ELBW neonates recruited into a two-center, prospective, cluster randomized study comparing ampicillin and penicillin both combined with gentamicin, within the first 72 h of life. A composite primary end-point (need for change of antibiotics within 72 h and/or 7 day all-cause mortality) and the rate and duration of colonization by opportunistic aerobic microorganisms were assessed using hierarchical models corrected for study center and period.

RESULTS

In the ampicillin (n= 36) and penicillin (n= 39) groups change of antibiotics, 7 day mortality and the composite end-point occurred at similar rates. Neonatal intensive care unit mortality for infants with gestational age <26 weeks was lower in the ampicillin group. Ampicillin treatment was associated with a higher colonization rate by Klebsiella pneumoniae, including ampicillin-resistant strains.

CONCLUSION

Preliminary data indicate an urgent need for adequately powered studies of early antibiotic therapy in the subpopulation of ELBW neonates at risk of EOS.