Colistin utilization at a tertiary hospital in South Africa: an opportunity for antimicrobial stewardship practices.

Introduction. Colistin (polymyxin E) has emerged as a last-resort treatment option for multidrug-resistant infections.Hypothesis/Gap Statement. Studies on the use, safety and efficacy of colistin in South Africa are limited.Aim. This study aims to describe the use of colistin and its clinical outcomes at a tertiary public hospital in South Africa.Methodology. We conducted a retrospective review of adult and paediatric patients who received parenteral colistin between 2015 and 2019.Results. A total of 69 patients (26 adults, 13 children and 30 neonates) were reviewed. Acinetobacter baumannii was the most common causative pathogen isolated (70.1 %). Colistin was predominately used to treat septicaemia (75.4 %). It was primarily administered as definitive therapy (71.0 %) and as monotherapy (56.5 %). It was used in 11.5 % of adults with infections susceptible to other antibiotics. Loading doses of intravenous colistin were administered in only 15 (57.7 %) adult patients. Neurotoxicity and nephrotoxicity occurred in 5.8 % and 43.5 % of patients, respectively. Clinical cure was achieved in 37 (53.6 %) patients. On multivariate logistic regression analysis, adults [adjusted odds ratio (aOR), 25.54; 95 % CI, 2.73-238.65; P < 0.01] and children (aOR, 8.56; 95 % CI, 1.06-69.10; P < 0.05) had higher odds of death than neonates.Conclusion. The study identified significant stewardship opportunities to improve colistin prescription and administration. Achieving optimal patient outcomes necessitates a multidisciplinary approach and vigilant monitoring of colistin use.