Antibiotic use in the neonatal unit.

The changing pattern of organisms causing neonatal sepsis, from Streptococcus pyogenes in the 1930s to Staphylococcus aureus in the 1950s and more recently to Gram negative bacilli and the group B streptococcus,' has been reflected in the development of new antibiotics. In particular semi-synthetic penicillins and the so called third generation cephalosporins have been introduced, both with activity against a wide range of Gram negative as well as some Gram positive organisms. There remains some uncertainty about whether it is best to use these antibiotics for all episodes of suspected sepsis or to reserve them for episodes not responding to more conventional antibiotics. In a recent survey of antibiotic use in neonatal units in the United Kingdom and Eire, conducted through the British Association of Perinatal Paediatrics, replies were received from 30 institutions, who regularly used 24 different antibiotic policies. This may reflect a rational approach to changing causes of sepsis and changing antibiotic resistance patterns but may equally be due to uncertainty over which of the many possible antibiotics to use. The aim of this article is to review antibiotic options in the light of known causes of neonatal sepsis and our experience and to give a rational explanation of our own antibiotic policies.