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

Pediatr Int. 2011 Dec;53(6):873-80. doi: 10.1111/j.1442-200X.2011.03468.x.


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.

Publication types

  • Comparative Study
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age of Onset
  • Ampicillin / administration & dosage*
  • Anti-Bacterial Agents / administration & dosage
  • Dose-Response Relationship, Drug
  • Female
  • Follow-Up Studies
  • Humans
  • Incidence
  • Infant Mortality / trends
  • Infant, Extremely Low Birth Weight*
  • Infant, Newborn
  • Intensive Care Units, Neonatal*
  • Intestines / microbiology
  • Klebsiella Infections / drug therapy*
  • Klebsiella Infections / epidemiology
  • Klebsiella pneumoniae / isolation & purification
  • Male
  • Penicillins / administration & dosage*
  • Prospective Studies
  • Risk Factors
  • Sepsis / drug therapy*
  • Sepsis / epidemiology
  • Treatment Outcome


  • Anti-Bacterial Agents
  • Penicillins
  • Ampicillin