Background. Organisms causing neonatal sepsis differ by region and the organisms causing sepsis change over time in the same area. The antibiotic susceptibility of microorganisms also changes with time, with emergence of multidrug resistant organisms.

Objective. This study aimed to review the causes of neonatal sepsis and antibiotic sensitivity of organisms causing neonatal sepsis at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH) neonatal unit over a 12-month period.

Methods. This was a retrospective descriptive study. All blood cultures obtained from the neonatal unit at CMJAH between 1 January 2012 and 31 December 2012 were reviewed. This was followed by a review of the clinical data of patients with a positive culture.

Results. During the period under study, there were 196 patients with blood-culture-proven neonatal sepsis. This gave an incidence of 10.3 per 100 admissions. Late-onset sepsis accounted for 83.7% of cases of neonatal sepsis. The predominant isolates were Klebsiella pneumoniae (32.2%), coagulase-negative Staphylococcus (23.7%) and methicillin-resistant Staphylococcus aureus (13.1%). The majority of the isolated K. pneumoniae were extended-spectrum beta-lactamase (ESBL) producing bacteria with resistance to ampicillin and gentamicin.

Conclusion. Neonatal sepsis is a common problem at the CMJAH neonatal unit. There has been an increase in the predominance of Gramnegative microorganisms as a cause of neonatal sepsis in the CMJAH neonatal unit over recent years, with ESBL-producing K. pneumoniae and Acinetobacter baumannii being the most prevalent Gram-negative causative agents of neonatal sepsis. Coagulase-negative Staphylococcus spp. remains an important cause of neonatal sepsis, and is the most prevalent Gram-positive organism isolated from the neonatal unit at CMJAH. Resistance to commonly used antibiotics regimens was noted to be high in the unit.