TSH-SECRETING PITUITARY ADENOMA PRODUCING SEVERETHYROTOXICOSIS WITH CACHEXIA AND ATRIAL FIBRILLATION,COMPLETELY CURED AFTER PITUITARY SURGERY

摘要

A 63-years old patient with severe thyrotoxicosis with cachexia and high frequency atrial fibrillation showed an inadequate secretion of TSH. A pituitary macroadenoma was revealed by computed tomography. Acute octreotide administration decreased serum TSH from 2.48 mU/mL to 0.06 mU/mL and T3 from 3.1 ng/mL to normal values (0.93 ng/mL) in 3 days; at the same time serum T4 remained unchanged (raised).The response to octreotide supported the diagnosis of TSH-secreting adenoma. T3 suppression test is no longer useful at present for diagnosis. Administration of long- acting somatostatin analogues (lanreotide) together with antithyroid drugs (ATD) was initially necessary. However, after removal of pituitary tumor the clinical symptoms (including atrial fibrillation) disappeared. ATD administration was no longer necessary, nor was octreotide or lanreotide. Immunohistochemistry certified that the pituitary tumor was a pure thyrotropinoma (without plurihormonal expression). Complete cure of severe thyrotoxicosis due to a TSH-secreting pituitary adenoma by pituitary surgery is possible. Thyroidectomy is not indicated.