UREMIC SMALL-ARTERY DISEASE WITH MEDIAL CALCIFICATION AND INTIMAL HYPERPLASIA (SO-CALLED CALCIPHYLAXIS) - A COMPLICATION OF CHRONIC-RENAL-FAILURE AND BENEFIT FROM PARATHYROIDECTOMY

Background: Uremic small-artery disease with medial calcification and intimal hyperplasia can lead to life-threatening skin necrosis or acral gangrene. It is a distinct complication of chronic renal failure that must be differentiated from soft-tissue calcification. An increased calcium-phosphate product and secondary hyperparathyroidism are the main underlying conditions. The benefit of parathyroidectomy is controversial. Objective: This article is based on a literature search to determine prognostic factors and, in particular, the benefit of parathyroidectomy. Methods: The literature on uremic small-artery disease (so-called calciphylaxis) was reviewed (full data set: 104 cases, including five of our own). The therapeutic benefit of parathyroidectomy and the relation between prognostic predictors (localization, dialysis, and renal transplant) and outcome were analyzed. The relation between diabetes and acral gangrene was also examined. Further epidemiologic data on the reviewed group of patients were established. Results: Thirty-eight of 58 patients who underwent parathyroidectomy survived compared with 13 of 37 patients who did not undergo parathyroidectomy (p=0.007, n=95). Forty of 53 patients with distal localization of necrosis survived compared with 11 of 42 patients with proximal pattern (p<0.00001; n=95). Dialysis and kidney transplantation followed by immunosuppression showed no relation to disease outcome. No association was found between diabetes and acral gangrene (p=0.50). Conclusion: Uremic small-artery disease is a distinct complication of chronic renal failure. Its recognition and early diagnosis should allow more effective treatment, In our retrospective study parathyroidectomy was significantly related to survival. Only a randomized, controlled, prospective trial (parathyroidectomy vs conservative treatment of secondary hyperparathyroidism) can establish the value of parathyroidectomy in uremic small-artery disease.