Leech Therapy (Bdellotherapy) for Frostbite: From Ancient Lore to Clinical Gold—A Clinical Evidence Appraisal of Tissue Salvage and Microcirculatory Regeneration

Abstract

Background: Frostbite is a cold-induced injury involving the freezing of tissues, leading to microvascular pathology characterized by ice-crystal formation, cellular dehydration, endothelial injury, and subsequent microvascular thrombosis and ischemia. The current management approach is often underexplored, with reliance on adult-derived protocols, which is concerning due to the potential for significant long-term morbidity. In Unani Medicine, frostbite is linked to Sue Mizaj Barid wa Ratb (cold and moist humoral imbalance). Bdellotherapy (medical leech therapy) is a classical intervention aimed at restoration via Tanqiya-e-Mawad (elimination of morbid matter). The scientific basis for this is strong, as leech saliva contains more than hundred bioactive compounds like hirudin, hyaluronidase, and calin that provide anticoagulant, anti-inflammatory, and microcirculatory-enhancing effects, suggesting its potential in frost bite. To establish clinical utility and inform guidelines, we propose rigorously designed randomized controlled trials with predefined outcome measures and safety monitoring.

Methods: This was a single-group, open-label clinical study conducted on 62 patients (aged 12–62 years) diagnosed with frostbite of the feet. Each participant received a total of five weekly sessions of Bdellotherapy with three leeches applied per sitting. Safety was monitored using baseline and post-treatment laboratory investigations (CBC, ESR, BT, CT, and Serum Electrolytes). Clinical efficacy was assessed across five weekly visits using the Visual Analogue Scale (VAS) for pain and the 5-D Pruritus Scale for itching. Data analysis utilized Repeated Measures ANOVA, with a significance level set at p < 0.05.

Results: Significant improvement was observed across all clinical parameters following Bdellotherapy. Mean VAS scores reduced progressively from baseline to the fifth session, indicating substantial pain relief (F = 101.62, p < 0.001). Similarly, mean 5-D Pruritus scores showed a significant decline (F = 67.30, p < 0.001). No adverse haematological or systemic effects were reported. All patients remained symptom-free during a 12-month follow-up. Conclusion: Bdellotherapy demonstrated statistically and clinically significant efficacy in alleviating frostbite-related pain, itching, and tissue ischemia among pediatric patients. The findings validate the traditional Unani approach through modern clinical evidence, suggesting that leech therapy may serve as a safe, effective, and natural alternative in frostbite management.