Urinary Adenosine 3',5'-Monophosphate, Circulating Amino-Terminal PTH (1�34) and Carboxyl-Terminal PTH in Hypoparathyroidism

In 38 patients with hypoparathyroidism, electrolytes, amino-terminal PTH(1--34) and carboxyl-terminal PTH in serum and urinary cyclic AMP were measured. Serum PTH(1--34) levels were low and C-PTH levels measured simultaneously in the same sera were low except one having a high level. In pseudohypoparathyroidism, serum C-PTH was elevated and in 1 of 2 patients serum PTH(1--34) was elevated. Urinary cyclic AMP was decreased in hypoparathyroidism and there was a positive correlation between urinary cyclic AMP and serum PTH in normal subjects and parathyroid dysfunctions. Responses of urinary cyclic AMP to PTH were better in hypoparathyroidism and less in primary hyperparathyroidism than normal subjects. These data suggest that measurements of serum PTH(1-34), C-PTH and urinary cyclic AMP are important in the diagnosis and pathophysiological classification of hypoparathyroidism.