BIOCHEMICAL MARKERS FOR NONINVASIVE DIAGNOSIS OF HYPERPARATHYROID BONE-DISEASE AND ADYNAMIC BONE IN PATIENTS ON HEMODIALYSIS

The diagnostic and predictive value of serum intact parathyroid hormon e (iPTH) and osteocalcin (bone Gla protein, BGP), alone or in combinat ion, have been examined in only a small number of haemodialysis patien ts. Methods. We studied prospectively 114 patients (46 women, 68 men; mean age 52 +/- 12 years) on regular haemodialysis for a mean of 55 (6 -185) months. All patients underwent labelled transiliac bone biopsy, and serum levels of iPTH, BGP and alkaline phosphatase were determined . Results. Seventy-one patients (62%) showed histological findings of hyperparathyroid bone disease, 24 (21%) mixed bone disease, six (5.5%) osteomalacia and 13 (11.5%) adynamic bone. Bone aluminium deposition over more than 25% of the trabecular bone interface was found in 66 pa tients (58%). Serum iPTH and BGP correlated with the majority of histo morphometric indices of bone formation, mineralization and resorption (r > 0.5, P < 0.01). iPTH levels greater than or equal to 200pg/ml and BGP greater than or equal to 50ng/ml were found to be indicative of h yperparathyroid bone disease, whilst iPTH levels < 65 pg/ml and BGP < 20 ng/ml were indicative of adynamic bone. However, the positive predi ctive value of these indices was limited (less than 80%, although thei r negative predictive value, especially when used in combination, was good (more than 90%) and the exclusion of hyperparathyroid bone diseas e and adynamic bone was possible. The diagnostic and predictive value of these bone markers were improved when patients with bone aluminium deposition were excluded. Conclusions. Diagnosis of hyperparathyroid b one disease and adynamic bone is difficult on the basis of iPTH and BG P, especially when bone aluminium deposition is prevalent. However, us ing these bone markers, preferably in combination, the exclusion of th ese lesions is feasible. adynamic bone; diagnostic and predictive valu e; intact parathyroid hormone; osteocalcin.