Bacteriology of diabetic foot ulcers

Area of Science:

• Microbiology
• Infectious Diseases
• Podiatry

Background:

• Diabetic foot ulcers are a significant complication of diabetes mellitus.
• Bacterial infections are a major cause of morbidity and mortality in diabetic foot ulcers.
• Understanding the polymicrobial nature of these infections is crucial for effective treatment.

Purpose of the Study:

• To identify the aerobic and anaerobic bacterial isolates from diabetic foot ulcers.
• To determine the antibiotic susceptibility patterns of these isolates.
• To guide appropriate antibiotic therapy for diabetic foot infections.

Main Methods:

• Seventy-five diabetic foot ulcers were cultured using optimal aerobic and anaerobic microbiologic techniques.
• Bacterial isolates were identified and quantified.
• Antimicrobial susceptibility testing (antibiogram) was performed for common antibiotics.

Main Results:

• A total of 223 isolates were recovered, with an average of 2.97 bacterial species per specimen.
• Staphylococcus aureus was the most frequent isolate (60%).
• Anaerobic organisms were found in 61.33% of patients, with Bacteroides fragilis being the most common anaerobe.
• Mixed bacterial infections were prevalent.
• Antibiogram revealed resistance to commonly used antibiotics.
• Metronidazole and gentamicin demonstrated the highest efficacy against anaerobic and aerobic isolates, respectively.

Conclusions:

• Diabetic foot ulcers are frequently polymicrobial, involving both aerobic and anaerobic bacteria.
• There is a concerning pattern of antibiotic resistance.
• Metronidazole and gentamicin are effective agents for treating anaerobic and aerobic infections in diabetic foot ulcers, respectively.
• Knowledge of causative organisms and their sensitivities is essential for optimal therapeutic strategies.