Ask the Experts - Management of Renal Transplant Recipient With...
I have a patient 9 months post renal transplantation who has developed calciphylaxis and had pretransplant hyperparathyroidism that is now controlled. Any thoughts about pathogenesis and treatment options?
Calciphylaxis is a complex syndrome characterized by painful skin lesions associated with necroses, ulcerations, and subcutaneous nodules. Skin biopsies of patients with calciphylaxis show medial calcifications and intimal proliferation in small arteries. Calciphylaxis is associated with high morbidity and mortality and has been described in patients with end-stage renal disease on hemodialysis as well as following transplantation.
The pathogenesis and the risk factors associated with calciphylaxis have not been well characterized, but several studies have suggested an association with elevated parathyroid hormone levels and increased calcium-phosphate products. In a recent study by Ahmed and colleagues, histologic examination suggests that the calcification is associated with increased expression of osteopontin by smooth muscle cells.
In a recent study by Mazhar and colleagues of calciphylaxis in patients with renal disease on hemodialysis or after transplantation, strong predictors for the development of calciphylaxis included female gender, low serum albumin level, elevated serum phosphate level, and elevated serum alkaline phosphatase level. Parathyroidectomy appears to be the only effective therapeutic modality that halts the progression of the disease and improves its outcome. In transplant patients who developed calciphylaxis, parathyroidectomy, even in the absence of hypercalcemia, can lead to healing of the skin lesions and prevent death from sepsis.