Grouping of patients with hyperparathyroidism by clinical signs, correlated to some biochemical findings

Serum parathormone (S-PTH), total and free fractions of serum calcium (Cat and Caf), urinary excretion of cyclic 3',5'-adenosine monophosphate (cAMPu), serum phosphate and serum magnesium were analysed in 68 patients with hyperparathyroidism verified by operation and PAD. The diagnostic significance of the analyses was examined. It was shown that Caf was consistently above normal even in patients in whom the other tests were normal. The best diagnostic sensitivity was thus found for Caf followed by Cat, S-PTH and cAMPu. The results of these tests were generally correlated to each other except in patients with impaired renal function in whom S-PTH increased out of porportion to the other tests. Cat and Caf were significantly correlated to each other. However, Caf was pathologic even when Cat was normal. It is concluded that for hypercalcemic patients Cat and Caf are the most reliable tests. S-PTH is elevated only in some hypercalcemic patients. In normocalcemic patients all tests except Caf show normal values.