Prospective follow-up study in patients with renal osteopenia

In a follow-up study of renal osteopathy (low-turnover osteopathy/osteopeni a) in patients on chronic hemodialysis measurement of the activity of the b one specific alkaline phosphatase has been proven to be apt besides the mea surement of the intact parathormon levels to assess the possibility to stim ulate bone formation. The concentrations of osteocalcin and of the procolla gen type I carboxyterminal propeptide are correlated with the activities of the bone specific alkaline phosphatase and therefore they allow to assess the amount of bone formation. Dialysate with low calcium contents of 1.0 - 1.25 mmol/l supports the stimulation of the bone metabolism in patients wit h low-turnover osteopathy/osteopenia but the activity of the bone specific alkaline phosphatase (cut-off > 45IU/l) has to be considered. The bone spec ific alkaline phosphatase activity is a suitable clinical parameter for pre dicting and recognizing an overstimulation of the bone in due time. The act ivity of the bone specific alkaline phosphatase is a more sensitive paramet er than the concentration of the intact parathormon and in low-turnover its overstimulation should be avoided. Furthermore a vitamin D-3 deficiency ha s to be corrected. A substitution, no suppression, of calcitriol and of cal cifediol should be done in low turnover osteopathy/osteopenia.