[Bone and bone related biochemical examinations. Significance of measurement of serum calcium, phosphorus, alkaline phosphatase, corrected calcium and urine calcium].

Classical clinical calcium endocrinology was built on measurements of serum Ca, P and alkaline phosphatase as well as urinary Ca. Serum Ca, the most strictly maintained biological constant, occupies the central role among them, controlling PTH secretion and bone metabolism. Ca is strongly bound to proteins especially albumin, so that total serum Ca values are sometimes misleading, necessitating the use of corrected or ionized Ca. Serum Pi rises early in renal insufficiency, playing an important role in vascular calcification. Growth hormone and thyroid hormone functions are also reflected on serum P. Serum alkaline phosphatase especially the bone-specific type is also important for the evaluation of bone dynamics such as growth and tumor metastasis. These classical datasets should be reevaluated in the light of actions of new compounds such as calcimimetics, P-binders, bisphosphonates, vitamin D derivatives, cytokines, etc.