Neonatal sepsis in a tertiary unit in South Africa.

BACKGROUND

Antimicrobial resistance (AMR) has emerged as a global threat to healthcare resulting in an increase in morbidity and mortality. Neonatal sepsis is ranked as the third highest cause of neonatal demise globally, in which AMR accounted for 31.0% of deaths. AMR in neonates has been poorly characterised in Durban, South Africa. Thus, the resultant effect of AMR on empiric regimens for neonatal sepsis is uncertain in this setting. Therefore, this study analysed the aetiology and antimicrobial susceptibility patterns of bloodstream infections within the neonatal intensive care unit at a tertiary hospital in Durban, with the aim of establishing an effective empiric regimen for the unit.

METHODS

A retrospective data review on positive blood cultures from the neonatal intensive care unit at Inkosi Albert Luthuli Central Hospital was conducted. Three time periods were analysed: 2014, 2016 and 2018. Culture data from neonates aged 0-30 days were included and repeat cultures were de-duplicated. The frequency of common organisms and their antimicrobial susceptibilities were analysed. Fischer's exact test was used for subgroup analysis. Poisson and logistic regressions were used to assess significant trends in organisms and antimicrobial susceptibilities over time.

RESULTS

Late-onset sepsis (86.8%) predominated over early-onset sepsis (13.2%). A preponderance of gram-positive organisms (68.7%) over gram-negatives (26.8%) and fungi (4.5%) was detected. Common pathogens included coagulase-negative staphylococci (53.5%), Klebsiella pneumoniae (11.6%), enterococci (9.3%), and Acinetobacter baumannii (7.7%). Despite the small contribution of fungi to the microbial profile, fluconazole-resistant Candida parapsilosis predominated within that group. High rates of resistance to first- and second-line antibiotics were also noted among gram-positive and gram-negative organisms. Multidrug resistant organisms included extended-spectrum beta-lactamase (ESBL) K. pneumoniae (7.6%) and extensively-drug resistant A. baumannii (7.0%). However, a statistically significant decrease in ESBL-producing organisms was documented during the entire study period (p = 0.005).

CONCLUSIONS

It was determined that first-line antimicrobials, advocated by the World Health Organization for treatment of neonatal sepsis, proved ineffective in this unit due to high levels of AMR. Therefore, this study advises that meropenem with or without vancomycin provides optimal empiric cover. Amphotericin B is advocated for empiric antifungal therapy. Ongoing surveillance is necessary.