Prolactin-producing pituitary adenoma in a 9 year old boy.

A boy aged 9 years and 8 months was evaluated for headache and an enlarged sella. His neurological status and visual fields were normal. After injection of radiographic contrast agent, computerized axial tomography showed evidence of an intrasellar tumor. The most striking endocrine abnormalities were growth hormone insufficiency after arginine infusion and after insulin-induced hypoglycemia, and excessively elevated prolactin levels ranging between 1220 ng/ml and 1560 ng/ml. A slightly granulated, acidophilic pituitary adenoma was selectively removed by the trans-sphenoidal approach. The function of the anterior pituitary improved post-operatively. Growth hormone secretion after insulin-induced hypoglycemia returned to normal, and the basal serum prolactin levels decreased, but are still three times higher than normal.