Bacteriological Profile and Antimicrobial Resistance Patterns of Pathogens Isolated from Patients with Infected Diabetic Foot Ulcers in Kisumu County, Kenya

Background: Diabetic foot ulcers (DFUs) are a significant complication of diabetes and are frequently associated with bacterial infections that hinder healing and increase the risk of antimicrobial resistance (AMR). However, local data on pathogen distribution and resistance patterns remain limited in many resource-constrained settings. Methods: A cross-sectional study was conducted from March to June 2025 across three referral hospitals in Kisumu County, Kenya. A total of 471 patients with DFUs were recruited using a stratified sampling approach. Specimens were processed in accordance with the Clinical and Laboratory Standards Institute (CLSI) 2025 guidelines. Bacterial identification was performed using standard biochemical methods, and antimicrobial susceptibility testing was conducted using the Kirby–Bauer disk diffusion technique. Results: Out of 471 participants, 202 had culture-positive infections, yielding 221 bacterial isolates. Gram-negative organisms predominated, accounting for the majority of isolates. Escherichia coli and Acinetobacter baumannii were the most frequently isolated Gram-negative pathogens. Among Gram-positive bacteria, Staphylococcus aureus was the leading isolate and exhibited multidrug resistance (MDR). Conclusion: The predominance of Gram-negative pathogens and the presence of multidrug resistance highlight the limitations of empirical therapy in DFU management. These findings underscore the importance of routine microbiological testing and targeted antimicrobial stewardship strategies.