Pseudohypoparathyroidism associated with hypercalcitoninaemia.

A case of a 33 year old man with type I of pseudohypoparathyroidism associated with hypercalcitoninaemia and deficiency of prolactin and growth hormone is reported. The diagnosis of pseudohypoparathyroidism was made by recognition of the classic skeletal signs of Albright's osteodystrophy and confirmed by an infusion test with parathyroid hormone, which revealed a lack of both a cyclic AMP and phospaturic response. By investigation of the endocrine status the function of the pituitary/thyroid and pituitary/testis axes as well as the adrenal cortex was observed to be normal. The basal prolactin concentration was however, lower than normal and a lack of response in the growth hormone level in two glucagon tests was observed. Furthermore the basal calcitonin level was higher than normal and by provacation with pentagastrine the calcitonin secretion was very high despite an only slightly decreased serum calcium level. By operation the thyroid gland was normal and by light microscopy of a biopsy no signs of medullary carcinoma was observed. No good explanation for the high calcitonin basal level and secretion was found.