Oral Versus Intravenous Antibiotics for Residual Osteomyelitis After Amputation in the Diabetic Foot

The standard management for residual osteomyelitis following amputation in a diabetic foot infection includes a prolonged course of intravenous antibiotic agents. The purpose of this analysis was to investigate whether oral antibiotic therapy led to treatment failure more than intravenous antibiotic therapy for this indication. The primary endpoint was treatment failure within one year of the initial amputation, defined by re-operation for residual osteomyelitic infection or a remaining nonhealing wound at the surgical site. All patients received at least 4 weeks of antibiotics and were chosen for oral or intravenous route of administration by infectious disease specialists. Characteristics including age, sex, hemoglobin A1c, BMI, tobacco use, PVD, homelessness and IDSA classification were also assessed for influence on antibiotic success and failure. Of the 65 patients meeting inclusion criteria, treatment failure occurred in 32 and treatment success occurred in 33. Of the treatment failures, 17 (53%) were in the intravenous group, and 15 (47%) were in the oral group. The differences between the modalities of antibiotic administration and their failure rates were not found to be statistically significant (p = .28 (proportional difference: -14%, 95% confidence interval [CI]:−36% to 10%)).