[Results of bone scintigraphy, densitometry and radiography in secondary hyperparathyroidism in patients with chronic renal failure].

Unlabelled: Secondary hyperparathyroidism occurs frequently in patients with chronic renal failure (CRF). Cardinal manifestations in patients with secondary hyperparathyroidism involve also skeletal changes. Hence the aims of our studies were detailed investigations of bones using isotope scintigraphy (99mTc-MDP), densitometry (DEXA-Lunar) and radiography, in a group of 34 patients with advanced secondary hyperparathyroidism with very high PTH serum concentrations. Bone mineral density of radius amounted to 74.14 +/- 14%, and 29 cases had osteoporosis, and 5 cases osteopenia. Bone mineral density of vertebral bodies was 85.6 +/- 10.5% was within osteopenia range in 16 cases, osteoporosis in 11 cases and was normal in 6 cases. Bone scintigraphy revealed: excessive tracer uptake in cranial vault, mandible, spine and lateral parts of the sacral bone. Tracer accumulation was decreased in soft tissues and absent in kidneys. Roentgen studies revealed changes typical to secondary hyperparathyroidism: acroosteolysis in 60% of cases, subperiosteal resorption in 43% of cases, calcifications in 20% of cases, cortical fibrosis in 35% of cases and osteoporosis in 85% of cases.

Conclusions: 1. Bone mineral density is markly decreased in the radius and to a lower extent in the vertebral bodies, hence DEXA studies of radius are most appropriate for evaluation of mineral bone density. The differences in BMD are characteristic of hyperparathyroidism, both primary and secondary. 2. In most patients bone scintigraphy shows characteristic abnormalities, thus scintigraphy is helpful in the diagnosis of advanced secondary hyperparathyroidism. 3. In x-ray studies osteoporosis is frequently observed, other signs of secondary hyperparathyroidism are not so common and appear in later stage of disease than decreased bone mineral density in densitometry.