Renal osteodystrophy. Radiological diagnosis compared with a new radioimmunoassay method of parathyroid hormone.

The parathyroid hormone concentration in the blood measured by the 'two-site radioimmunoassay', which is specific for the biologically active parathyroid molecule (parathyrine), was compared with the radiological manifestations of secondary hyperparathyroidism (HPT) on magnification radiographs of the phalanges in patients undergoing maintenance hemodialysis and in patients with renal allografts. Sensitivity of radiology for the diagnosis of HPT proved to be high (88%), whereas specificity was low (30%). Statistical analysis showed that there was a good correlation between the parathyrine levels and the intensity of radiological changes in the phalanges in patients with renal allografts (coefficient of Krueger-Spearman = 0.65). In patients undergoing hemodialysis the correlation between laboratory parameters and radiological changes was poor.