Analytical and diagnostic validity of biochemical markers of bone metabolism

A review ist given about bone turnover markers. These markers may be either measures of bone formation or bone resorption. Marker of bone formation are bone alkaline phosphatase, osteocalcin, carboxyl- end amino-terminal propeptides proteolytically cleaved in the extracellular space from type I procollagen, and other bone matrix proteins (e.g., bone sialoprotein). Markers of bone resorption ore pyridinium cross-links, destruction products from the telopeptide region of type I collagen, end tartrate resistant acid phosphatase. The parameters differ from each other with respect to preanalytical stability, biological influential factors and diagnostic specificity and sensitivity.