Objective: The diabetic foot is a frequent complication of diabetes mellitus. It confers a negative impact on the patients’ quality of life and profound burden on the healthcare system. The objectives of this study were to determine the bacteriological profile and antibiotic susceptibility of patients admitted to the University Hospital of the West Indies with diabetic foot ulcer over a 5-year period, and whether methicillin-resistant Staphylococcus aureus is a common microbial isolate and if antibiotic resistance played a role on the patients’ duration of hospital stay or amputation.
Methods: A retrospective analysis was done on the patients admitted from January 2003 to December 2008 with the diagnosis of diabetes mellitus and foot complications. The eligible patients and their medical records were identified by the medical records department. Their demographic data, types of cultures done and results, antibiotic susceptibility and resistance, and treatment regimens were all recorded. Frequency and means were calculated, and statistically significant covariates used as the predictors in univariate and multivariate regression models.
Results: Of the 545 cases admitted, 102 had complete data for analysis. Group D Streptococci was the most common organism isolated (45.1%) followed by other forms of Streptococci and Pseudomonas aeruginosa. The majority of cases (80.6%) had two or more bacterial isolates. Gram-negative bacteria (Proteus and Klebsiella) and anaerobes were also common, 48.0% and 22.5% respectively. There were no cases of methicillin-resistant Staphylococcus aureus. Antibiotic resistance was not significant.
Conclusion: Gram-positive organisms, especially the Streptococcus species, remain an important organism in diabetic foot infections. Current empiric antibiotic regimes used are effective in this tertiary care university hospital.