DIABETIC FOOT INFECTIONS - BACTERIOLOGY AND ACTIVITY OF 10 ORAL ANTIMICROBIAL AGENTS AGAINST BACTERIA ISOLATED FROM CONSECUTIVE CASES

OBJECTIVE - To study the relative frequency of bacterial isolates cult ured from community-acquired foot infections and assess their comparat ive in vitro susceptibility to sparfloxacin, levofloxacin, and eight o ther commonly used oral antimicrobial agents. RESEARCH DESIGN AND METH ODS - This is a prospective study in which the infected wounds of 25 c onsecutive diabetic patients seen by one of the authors were cultured as they entered the hospital. Isolates were stored and tested for susc eptibility to 10 oral antimicrobial agents using the agar dilution met hod. RESULTS - Staphylococcus aureus was the most common isolate (76% of patients), including methicillin-resistant S. aureus (MRSA) in 5 of 25 (20%) patient wounds. Streptococci, enterococci, Enterobacteriacea e, and anaerobes were also present in greater than or equal to 40% of patient wounds. Sparfloxacin and levofloxacin were the most active age nts tested with activity against greater than or equal to 88% of isola tes. Isolates resistant to sparfloxacin and levofloxacin included MRSA , enterococci, and some anaerobes. When analyzed by prior exposure to antibiotics, patients who had previously received oral antibiotics wer e more likely to have MRSA, enterococci, and Pseudomonas aeruginosa is olated and less likely to have Enterobacteriaceae and anaerobes isolat ed from their wounds. CONCLUSIONS - MRSA and enterococci are now a com mon cause of diabetic food infections, and the increased prevalence ma y be due to antimicrobial use. These wounds may require use of combine d antimicrobial therapy for initial outpatient management. The new flu oroquinolones, sparfloxacin and levofloxacin, were the most active ora l agents tested.