Topical Application of a Gentamicin-Collagen Sponge Combined with Systemic Antibiotic Therapy for the Treatment of Diabetic Foot Infections of Moderate Severity

Abstract

The aim of this pilot study was to determine the safety and potential benefit of adding a topical gentamicin-collagen sponge to standard of care (systemic antibiotic therapy plus standard diabetic wound management) for treating diabetic foot infections of moderate severity. We randomized 56 patients with moderately infected diabetic foot ulcers in a 2:1 ratio to receive standard of care plus the gentamicin-collagen sponge (treatment group, n = 38) or standard of care only (control group, n = 18) for up to 28 days of treatment. Investigators performed clinical, microbiological, and safety assessments at regularly scheduled intervals and collected pharmacokinetic samples from patients treated with the gentamicin-collagen sponge. Test of cure was clinically assessed 14 days after all antibiotic therapy was stopped. On treatment day 7, we noted clinical cure in no treatment patients and three control patients (P = .017). However, for evaluable patients at the test-of-cure visit, the treatment group had a significantly higher proportion of patients with clinical cure than did the control group (22 of 22 [100.0%] versus 7 of 10 [70.0%]; P =.024). Patients in the treatment group also had a higher rate of eradication of baseline pathogens at all visits (P ≤ .038) and a reduced time to pathogen eradication (P < .001). Safety data were similar for both groups. Topical application of the gentamicin-collagen sponge seems safe and may improve clinical and microbiological outcomes of diabetic foot infections of moderate severity when combined with standard of care. These pilot data suggest that a larger trial of this treatment is warranted.