Where do soft tissue calcifications occur in renal osteodystrophy?
Soft tissue calcification is common in renal osteodystrophy. Sites of soft tissue deposition are multiple, including the cornea and conjunctiva, viscera, vasculature, and subcutaneous and periarticular tissues. Calcification consistently occurs in chronic renal failure when the concentration (mg/dL) product of plasma calcium and phosphorus exceeds 70. It can also occur at lesser levels. Of particular concern is the high incidence of coronary artery calcification in patients on hemodialysis, which can predispose them to coronary events. Additionally, vascular calcification may compromise blood flow leading to ischemic necrosis of skin and muscle, which is called calciphylaxis . The chemical composition of the calcium depends on the site of deposition. In subcutaneous, vascular, and periarticular sites, hydroxyapatite is observed, whereas in viscera, a magnesium whitlockite-like material is found.
