Outpatient Parenteral Antibiotic Therapy for Diabetic Foot Osteomyelitis in an Uninsured and Underinsured Cohort.

ABSTRACT

Background: Diabetic foot osteomyelitis (DFO) is usually treated with prolonged outpatient parenteral antibiotic therapy (OPAT). Evaluation and treatment of non-antibiotic aspects of DFO (e.g., peripheral artery disease [PAD]) are also recommended. There is limited data regarding OPAT practice patterns and outcomes for DFO. Methods: Single-center observational study of patients receiving OPAT for DFO in a large United States public hospital between January 2017 and July 2019. We abstracted data regarding microbiology test, antibiotics, clinical outcomes, and non-antibiotic DFO management. Results: Ninety-six patients were included and some had >1 DFO-OPAT course during the study period (106 DFO-OPAT courses included). No culture was obtained in 40 (38%) of courses. Methicillin-resistant S. aureus (MRSA) was cultured in 15 (14%) and P. aeruginosa in 1 (1%) of DFO-OPAT courses. An antibiotic with MRSA activity (vancomycin or daptomycin) was used in 79 (75%) of courses and a parenteral antibiotic with anti-pseudomonal activity was used in 7 (6%) of courses. Acute kidney injury occurred in 19 (18%) DFO-OPAT courses. An ankle-brachial index measurement was obtained during or 6 months prior to the first DFO-OPAT course for 44 (49%) of patients. Forty-two (44%) patients died or had an amputation within 12 months of their initial hospital discharge. Conclusions: We found high rates of empiric antibiotic therapy for DFO and low uptake of the non-antibiotic aspects of DFO care. Better implementation of microbiological tests for DFO in addition to stronger integration of infectious disease and non-infectious diseases care could improve DFO outcomes.