The Burden of Nosocomial Neonatal Sepsis at the Chris Hani Baragwanath Academic Hospital using Conventional Culture Methods and Minimal Invasive Tissue Sampling

Abstract

Background: Neonatal sepsis is a clinical syndrome characterised by systemic signs of infection occurring within the first 28 days after birth, accompanied by the isolation of microorganisms in blood or cerebrospinal fluid (CSF) cultures. It can be categorised into early-onset sepsis (EOS) and late-onset sepsis. EOS occurs within the first 72 hours of life and usually results from vertical transmission of organisms from the mother, often occurring in utero. Late-onset sepsis occurs between 3 and 28 days and may be horizontally transmitted by the mother, other close contacts, or the community. Nosocomial neonatal sepsis, a subset of late-onset sepsis acquired within healthcare facilities, is associated with multiple factors and is often caused by pathogens such as Staphylococcus aureus, Klebsiella pneumoniae, and Acinetobacter baumannii. This type of sepsis is defined as occurring at least 48 hours after admission or birth. In Sub-Saharan Africa in 2017, a significant proportion of neonatal deaths (75%) occurred within the first seven days of life, with 50% occurring within the first 24 hours. This study aims to investigate the burden of nosocomial sepsis in neonates at Chris Hani Baragwanath Academic Hospital from 2016 to 2019, specifically focusing on cases caused by Methicillin-resistant Staphylococcus aureus, Klebsiella pneumoniae, and Acinetobacter baumannii. Methods: This was a retrospective descriptive study of the incidence, and laboratory and clinical characteristics of Acinetobacter baumannii, Klebsiella pneumoniae and Methicillin-resistant Staphylococcus aureus on blood and/or cerebrospinal fluid in neonates hospitalised (at least 48 hours after admission or birth) at the CHBAH from January 2016 to December 2019. We identified cases through the National Health Laboratory Services- Cooperate Data Warehouse database and cross-referenced that with the neonatal discharge database, and the extracted demographics, laboratory and clinical data. Results: Over the study period, we identified 859 culture-confirmed nosocomial neonatal sepsis caused by Acinetobacter baumannii (462; 53.8%), Klebsiella pneumoniae (323; 37.6%) and Methicillin Resistant Staphylococcus aureus (MRSA) (74; 8.6%). The incidence (per 1000 live births) of Acinetobacter baumanni and Klebsiella pneumoniae remained consistent over the study period, and was highest at 4.03 (95%CI: 3.36-4.80) and 2.91 (95%CI: 2.34-3.57) in 2017, respectively. The incidence of MRSA declined from 1.59 (95%CI: 1.16-2.13) in 2016 to 0.21 (95%CI: 0.08-0.43; p=<0.001). The case fatality rate was 54.5%, 40.6% and 31.1% for iii Acinetobacter baumannii, Klebsiella pneumoniae and MRSA respectively. Most (68.4%) neonates with Acinetobacter baumannii had very low birth weight and 162 (35.1%) were HIV-exposed. Similarly, a large proportion (52.0%) of neonates with Klebsiella pneumoniae were very low birth weight and 34.7% were HIV-exposed. Acinetobacter baumannii had an overall resistance of 71.9% to amikacin, 66% to cefepime, and 66.5% to ceftazidime. Conclusion: The incidence and case fatality rates of nosocomial Acinetobacter baumannii and Klebsiella pneumoniae were high in this setting, particularly amongst neonates with low birth weight. The study emphasises the need for improved infection prevention and control measures, antibiotic stewardship, implementation of enhanced therapeutic approaches, and efforts to minimise prolonged hospital stays.