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A Novel in vivo Gene Transfer Technique and in vitro Cell Based Assays for the Study of Bone Loss in Musculoskeletal Disorders
Published on: June 8, 2014
Modulation of renal osteodystrophy by extrarenal production of calcitriol
J A Delmez1, A S Dusso, E Slatopolsky
1Chromalloy American Kidney Center, Washington University School of Medicine, St. Louis, MO 63110-1093.
Abstract:
We report a patient with severe chronic renal failure who developed spontaneous bone fractures. He was found to have hypercalcemia, normal calcitriol levels (probably due to extrarenal production by noncaseating granulomas), and functional hypoparathyroidism. The bone biopsy showed low bone turn-over and the presence of noncaseating granulomas. Treatment with corticosteroids decreased the calcium and calcitriol levels and the parathyroid hormone levels rose. No further fractures occurred. A repeat bone biopsy revealed the presence of osteitis fibrosa. Renal osteodystrophy may be modulated by extrarenal production of calcitriol. In this case, excessive suppression of parathyroid hormone by endogenous calcitriol presumably caused an adynamic bone lesion and spontaneous fractures.
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