Trends in bloodstream infections and antimicrobial resistance among ICU patients with central venous catheters: A four-year retrospective study at Windhoek Central and Katutura Intermediate Hospitals (2020–2023)

• A four-year retrospective review analyzed blood culture data from ICU patients with central venous catheters. • Most sampled patients (96.8 %) had clinically significant bloodstream infections. • Staphylococcus epidermidis, Enterococcus faecium , and Klebsiella pneumoniae were the main pathogens. • High resistance was observed to ciprofloxacin (78 %), co-trimoxazole (74 %), and benzylpenicillin (81 %), while vancomycin and meropenem remained over 90 % effective. Bloodstream infections are a major cause of morbidity and mortality in Intensive Care Unit (ICU) patients, especially in resource-limited settings. This study aimed to evaluate the frequency of organisms isolated, antibiotic susceptibility patterns, and trends in multidrug resistance among ICU patients with central venous catheters at Windhoek Central Hospital and Katutura Intermediate Hospital from 2020 to 2023. A retrospective review of blood culture results was conducted using laboratory data from the Namibia Institute of Pathology for patients with central venous catheters, who had blood culture samples taken while admitted to the ICU. Data collected included organism identification, antibiotic susceptibility, and resistance patterns. Descriptive statistics were used to analyze trends across the four years. This is the first study to report on bloodstream infections and resistance patterns from Namibia. A total of 464 ICU patients had blood cultures performed, with 421 (96.8%) showing clinically significant infections. The most frequently isolated organisms were Staphylococcus epidermidis , Enterococcus faecium , and Klebsiella pneumoniae . High resistance rates were observed for ciprofloxacin, co-trimoxazole, and benzylpenicillin, while vancomycin and meropenem retained high efficacy. Multi-drug-resistant organisms were present in all four years, with Gram-positive organisms dominating the multi-drug resistance profile. The study shows high levels of bloodstream infections, antimicrobial resistance, and a persistent burden of MDR organisms in ICU settings. These findings support the need for stronger infection control, updated local antibiograms, and improved antimicrobial stewardship. Future research should include clinical data, molecular diagnostics, and a broader hospital network to guide more effective interventions.