[Renal osteodystrophy: the importance of 1-alpha-OH-D3].

Eighteen hemodialysed patients having a plasma calcium level of 2 mmol/l or less were treated by 1-alpha-OH-D3 at a mean dose of 1.56 microgram per day for six to twelve months. Calcium levels rose significantly. The concomitant rise in phosphorus levels required large doses of aluminum hydroxide. Alkaline phosphatase and parathormone levels were significantly lowered. Seven patients had calcium levels above 2.75 mmol/l and subsequently developed metastatic calcifications. Therefore plasma calcium levels should be carefully monitored during treatment and maintained at normal levels. In twelve cases bone histomorphometric studies were done. When bone demineralization is a prominent feature, satisfactory osteoid tissue mineralization can be obtained, while bone resorption remains unchanged.