CLINICAL USEFULNESS OF SERUM CARBOXYTERMINAL PROPEPTIDE OF PROCOLLAGEN-I AND TARTRATE-RESISTANT ACID-PHOSPHATASE DETERMINATIONS TO EVALUATEBONE TURNOVER IN PATIENTS WITH CHRONIC-RENAL-FAILURE

We have studied the levels of the biochemical markers of bone formatio n total serum alkaline phosphatase, osteocalcin (BGP) and carboxytermi nal propeptide of type I procollagen (PICP), the levels of the biochem ical marker of bone resorption serum tartrate-resistant acid phosphata se (TRAP) and those of intact immunoreactive PTH (iPTH) in 30 patients at different stages of chronic renal failure (CRF), all of them witho ut verifiable hepatopathy, and in 9 patients in hemodialysis with hepa topathy measured by the Knodell index. Sixteen control subjects were a lso studied. In the group of patients with CRF with or without hepatop athy, the levels of biochemical markers of bone turnover were signific antly elevated with respect to those of control patients. We did not f ind any significant difference in the levels of these parameters betwe en the groups with and without liver damage, in spite of the fact that TRAP and PICP are cleared mainly by the liver. Levels of TRAP and PIC P correlated significantly with the other biochemical markers of bone turnover studied. The good relation observed between PICP, TRAP and th e biochemical indexes of bone activity and iPTH levels suggests the cl inical value of these markers in the follow-up of bone involvement in patients with CRF. On the other hand, the frequent hepatopathy found i n patients with CRF does not seem to affect to a significant extent th e diagnostic value of PICP and TRAP in this pathology.