Trial of Sodium Thiosulfate (STS) in Penile Calciphylaxis

Introduction: Calciphylaxis is a rare, serious condition marked by vascular calcification, mainly in end stage kidney disease (ESKD) patients. Penile involvement causes ischemic necrosis, pain, and ulcers, with up to 44% mortality at one year. Risk factors include hyperphosphatemia, diabetes, use of warfarin, calcium-based binders and vitamin D analogs. STS offers potential benefits. Case Description: A 65-year-old male with insulin dependent diabetes and ESKD on peritoneal dialysis (PD) presented with sepsis like picture, complained of penile pain and whitish lesion that progressed to eschar over 48 hours. Labs showed elevated phosphorus and PTH. CT revealed penile vascular calcifications. STS was started but stopped 2 weeks later due to vomiting. Patient showed improvement in pain and wound healing after STS therapy and conservative care. Subsquently, patient was discharged but died 3 months later, showing no survival benefit despite healing. Discussion: Penile calciphylaxis is a rare and severe condition often associated with ESKD. It can mimic conditions like skin infections and peripheral vascular disease. Signs include painful, ulcerated lesions with black eschar. Biopsy is usually avoided due to poor healing. Imaging can aid diagnosis by revealing vascular calcification. Management includes wound care, pain control and correcting mineral imbalances, but outcomes are often poor, with risks of sepsis and penile auto-amputation. STS helps through binding to calcium forming calcium thiosulfate which is more soluble and easily eliminated, also through its anti-inflammatory and antioxidant effects. One systematic review outlines the use of STS in PD patients with calciphylaxis; despite some patients experiencing successful wound healing with STS, significant adverse effects and high mortality rates were observed. An additional review has reported that STS wasn't associated with skin lesion improvement or survival benefit in patients with chronic kidney disease with calciphylaxis. Further research is needed to establish standardized protocols, optimal dosing and long-term safety of STS in calciphylaxis.