Abstract
Predictive values of serum bone Gla-protein (BGP) and alkaline phosphatase (ALP) for bone histology were evaluated in 39 hemodialysis patients. All patients underwent bone biopsies, and serum levels of BGP and ALP were measured at the time of biopsy.
Osteoblastic activity correlated well with serum BGP, and somewhat less well with serum ALP. Serum BGP showed a highly significant correlation with the tetracycline labeling rate, corrected mineral appositional rate, and bone formation rate. These histomorphometric parameters were significantly correlated, but to a lesser degree, with serum ALP. Osteoclastic bone resorption was also correlated with serum BGP, but only marginally with serum ALP. Furthermore, serum BGP showed a significant negative correlation with the corrected mineralization lag time, bone formation period, the [resorption+reversal] period, and remodeling period. In contrast, weak correlations, of none at all, were found between serum ALP and these histomorphometric parameters.
The data indicate that serum BGP is a good marker for evaluating bone remodeling (bone resorption, formation and mineralization) in hemodialysis patients, and serum ALP mainly reflects bone formation activity by osteoblasts. Serum BGP seems to be a better index of bone turnover than serum ALP in hemodialysis patients.
