Antimicrobial resistance and genes profiles of Acinetobacter baumannii isolated from University Teaching Hospital of Kigali
INTRODUCTION: Antimicrobial resistance is a growing global threat, with carbapenem-resistant A. baumannii (CRAB) identified by World Health Organisation (WHO) as a top-priority pathogen. In Rwanda, data on resistance patterns and underlying genetic determinants in A. baumannii remains limited. This study aims to assess phenotypic resistance profile and detect key resistance genes to support infection prevention and control (IPC) and antimicrobial stewardship interventions. METHODS: A cross-sectional study was conducted from February to July 2025.Acinetobacter baumannii isolates were identified and tested for antimicrobial susceptibility using the disk diffusion method. Polymerase chain reaction (PCR) was used to detect selected resistance genes. Data on patient demographics, sample types, and hospital wards were collected and analysed. RESULTS: Of 1746 clinical isolates, 3.2% (n=56) were confirmed Acinetobacter baumannnii. Most isolates were recovered from male Intensive Care Unit (ICU) patients aged 19–40. All isolates showed 100% resistance to key beta-lactams, high resistance to ciprofloxacin with 87.0%, gentamicin 78.3%, while complete susceptibility to imipenem at 100% was observed. Resistance genes; blaOXA-23 and blaCTX-M were detected in 60.9% and 52.2% of isolates respectively, confirming the genetic basis for carbapenem and ESBL resistance. CONCLUSION: The study revealed a significant burden of multidrug-resistant Acinetobacter baumannii infections, particularly among ICU patients. The high resistance of blaOXA-23 and blaCTX-M highlights the complexity of managing these infections and underscores the need for strengthened IPC measures, routine molecular surveillance, and targeted AMS strategies.