| • | aka "calcifying panniculitis of renal failure" |
| • | a rare, life threatening complication of chronic renal failure |
| • | = a type of metastatic calcification |
| • | manifest by rapidly progressive calcification of small and medium-sized blood vessels |
| • | clinical: lesions typically described as violaceous pattern of livedo reticularis, which results in extensive cutaneous necrosis |
| • | etiology: unclear; believed that the secondary hyperparathyroidism of renal failure is a key contributing factor |
| • | patients tend to have high calcium X phosphorous products and secondary hyperparathyroidism (due to renal phosphate retention) |
| • | some patients do develop calciphylaxis with normal calcium and phosphorous levels |
| • | histology: mural calcification of small arterioles in the deep dermis and lobular areas of the subcutaneous tissue |
treatment:
| • | treatment is difficult, and therefore it is best prevented by management of elevated phosphorous levels with binding agents |
| • | treatment of choice may be: sodium thiosulfate = a calcium chelating agent, anecdotal evidence only |
| • | once lesions begin to appear, parathyroidectomy may be considered (often not effective) |
| • | in general, the extent of disease at onset predicts the outcome |
| • | distal type – if restricted to below mid-calf and the fingers, prognosis is good (70% survival) |
| • | proximal type – extensive lesions, 85% mortality – death usually from sepsis |
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