Intralesional sodium thiosulfate for the treatment of calciphylaxis.

IMPORTANCE: Calciphylaxis is a potentially fatal disorder of abnormal calcium deposition. Patients commonly present with painful retiform to stellate purpuric lesions that often undergo ulceration and necrosis, increasing the risk of infection and life-threatening sepsis. Treatment is multifaceted, and improved outcomes have been demonstrated with intravenous sodium thiosulfate; however, the use of this medication can be limited by its adverse effects. The use of topical sodium thiosulfate has been successfully reported for superficial calcium deposits in the skin from other processes. Therefore, we hypothesized that intralesional (IL) sodium thiosulfate may be an effective treatment for the deeper lesions of cutaneous calciphylaxis. We provide a retrospective case review of 4 patients with calciphylaxis who were treated with IL sodium thiosulfate. OBSERVATIONS: Four patients with biopsy-proven cutaneous calciphylaxis were treated with IL sodium thiosulfate (250 mg/mL) in areas of clinically active disease. The patients tolerated the medication well, with only transient localized discomfort during injection. All 4 patients had complete healing of their ulcers and remission of disease. CONCLUSIONS AND RELEVANCE: Intralesional sodium thiosulfate may be an effective and well-tolerated treatment for localized calciphylaxis. This novel approach requires further research and investigation.