Therapeutic effects of 25 hydroxyvitamin D₃ on renal osteodystrophy. Biochemical and morphometric analyses

5 patients with end-stage renal disease, undergoing hemodialysis were studied sequentially; the skeletal response to chronic 25OHD₃ therapy was quantitated histologically and compared to both bone collagen-mineral maturation profiles and bone mineral content. Biochemically, the bone mineral-collagen maturational profiles reverted toward normal in all 5 patients after 25OHD₃ therapy, and the bone calcium content as well as Ca/P ratio was increased, coincident with the clinical pattern of a progressive increase in intestinal calcium absorption and a decrease in circulating iPTH and alkaline phosphatase. In that bone maturational profile changes were highly significant in all patients following 25OHD₃ therapy, while histological changes were not striking in all patients, particularly in those with minimal pretreatment morphological evidence of osteodystrophy, measurements of mineral-collagen density-gradient profiles may prove complimentary to histometric analyses in detecting early skeletal changes in the uremic patient.