Comparative outcomes of standard wound care versus a triple-combination topical regimen including metronidazole in post-debridement necrotizing fasciitis wounds: a retrospective cohort study

Background: Necrotizing fasciitis (NF) is a rapidly progressive soft tissue infection requiring prompt surgical and antimicrobial management. While systemic antibiotics are essential, topical therapy may enhance local control. This study compares the clinical efficacy of standard topical therapy (saline+honey) versus a triple combination regimen (metronidazole, povidone iodine and hydrogen peroxide) in NF wound care. Methods: This retrospective cohort study analyzed 50 patients with NF treated at a tertiary center in Nigeria between January 2022 and March 2024. Patients were divided into two groups: a standard therapy group (n=25) and a triple-combination therapy group (n=25). Primary outcomes included final white blood cell (WBC) count, percent wound effluent reduction and time to granulation tissue appearance. Secondary outcomes were treatment success rate and need for repeat debridement. Independent t-tests and chi-square analyses were used. A p-value<0.05 was considered significant. Results: Baseline WBC counts were similar between groups (p=0.341). The triple-combination group achieved significantly lower final WBC counts (4,900±1234 cells/µl) compared to the standard group (5,125±1435 cells/µl; p=0.001). Wound effluent reduction was also greater in the triple group (81.97%±8.92) vs. standard (64.67%±10.11; p=0.001). Granulation tissue appeared earlier in the triple group (4.48±0.79 days) than in the standard group (6.89±1.98 days; p=0.001). Treatment success was significantly higher with triple therapy (84.0%) versus standard (56.0%; χ²=4.667, p=0.031). Conclusions: Triple-combination topical therapy with metronidazole, povidone iodine and hydrogen peroxide led to superior clinical outcomes compared to standard care, achieving faster infection resolution, enhanced wound granulation and higher treatment success rates. This approach may offer a cost-effective, accessible adjunct in NF care, particularly in resource-limited settings.