Growth hormone overproduction in a patient with multiple endocrine neoplasia type I

In a 69-year-old woman with a complicated history of multiple endocrine neoplasia type I (MEN 1), growth hormone overproduction was found without clinical features of acromegaly. Zollinger-Ellison syndrome was diagnosed at the age of 36 years. Total gastrectomy and partial pancreatectomy were performed. Two years later hypercalcaemia occurred, hyperparathyroidism was suspected and three hyperplastic parathyroid glands were removed. In 1994 the plasma gastrin level was elevated and a computerized tomography of the abdomen revealed a 1.5-cm large pancreatic tumour. Screening of the pituitary functions was unremarkable and a magnetic resonance scan of the pituitary gland showed no abnormalities. In 1995 type II diabetes mellitus was diagnosed. In 1997 basal plasma growth hormone levels were raised and plasma IGF-I levels were alternately high and normal. The patient had no clinical signs of acromegaly, but glucose tolerance testing resulted in a paradoxical rise in growth hormone concentration compatible with the diagnosis of growth hormone overproduction. Magnetic resonance imaging of the pituitary gland revealed a microadenoma.