Bacteriological and therapeutic profile of diabetic foot infection: a prospective study of 100 patients.

Background: Identifying the infecting bacterial flora is one of the main rules to be followed to ensure the success of antibiotherapy in the treatment of the infected diabetic foot. The aim of the work was to define the bacteriological profile of the bacteria causing the infection of the diabetic foot at the surgery unit B of Charles Nicolle's hospital in Tunis and determine the prognostic factors of this condition.

Methods: It was an open prospective study. It concerned 100 diabetic patients operated on for diabetic foot infection. All patients had bacteriological samples taken through deep scraping and swabing carried out in the operating room.

Results: The average age of patients was 59,5 ±11 years, with a sex-ratio of 2,4. The foot infection was represented in 82 % of cases by a wet gangrene. The enterobacteria were the most frequently isolated bacteria (73%), followed by streptococcus (10%), Staphylococcus aureus (9%). The rate of multidrug-resistant bacteria was of 9,5%. The empiric antibiotic therapy used (fusidic acid +amoxicillin/ clavulanic acid) was inactiveon 44,1% of the isolated bacteria. When we compared the group of patients with unfavourable development (who have been reoperated) and the group of patients with favourable development, we have found two poor prognosis factors : arteritis  (p=0,018 ; OR=23,7) and presence of multidrug-resistant bacteria (p=0,027 ; OR=5,8).

Conclusion: The enterobacteria were the main bacteria causing the infection of diabetic foot. The prognostic factors found, arteritis and isolation of multidrug-resistant bacteria, outpoint the importance of multidisciplinary care.