Endocrine Abstracts

Abstract: A 14-yr-old male patient with acromegaly and TSH-induced hyperthyroidism is reported. He was referred for hormonal study due to clinical suspicion of acromegaly. Physical examination showed acromegalic/gigantism features (high stature: 194.5 cm (P>90), such as: abnormal growth of the hands and feet, furrowed forehead and pronounced brow ridge). No goiter was found. GH levels were high and were not suppressed after oral glucose (GH: 12.50 ng/ml, GH after glucose: 6.19 ng/ml; IGF-1: 1391 ng/ml); Serum thyroid hormones levels were high, although TSH levels were not suppressed (TSH: 0.96 mU/ml, T4: 3.57 ng/dl T3: 11.06 pg/ml). Antithyroglobin, antimicrosomal autoantibody, and TSH receptor antibody were negative. Gonadotropines, prolactine and ACTH leves were normal (Prolactina: 12.79 ng/dl, LH: 9.37, FSH: 4.56, Testosterona: 760.9 ng/dl, Cortisol: 5.9 mcgr/dl, ACTH: 15.1 pg/ml). A pituitary magnetic resonance imaging of the pituitary revealed a 7-mm adenoma. He was diagnosed of acromegaly and hyperthyroidism. Pre-operative treatmen with octreotide was iniciated and transsphenoidal surgery was performed to remove the pituitary adenoma. Post-operative serum thyroid hormone and GH levels returned to normal, and IGF-1 levels were still elevated (786 ng/ml). Immunohistochemical staining of the operative specimen showed positive reactions to both TSH and GH. Pituitary gigantism is a rare condition caused by growth hormone secreting pituitary tumor. Choromophobe adenoma producing either acromegaly and hyperthyroidism have been described in a limited number of cases none of them on an infant.