A case of TSH-secreting pituitary adenoma with cyclic fluctuations in serum TSH levels.

A case of TSH-secreting pituitary adenoma with cyclic fluctuations in serum TSH levels. Endocr J. 2018 Apr 26;: Authors: Okuma H, Hashimoto K, Ohashi T, Mihara M, Minami I, Izumiyama H, Sasaki S, Inoshita N, Nishioka H, Yamada S, Yoshimoto T Abstract A 29-year-old man was referred to our department due to adrenal insufficiency with the inappropriate secretion of TSH (SITSH). Magnetic resonance imaging revealed a pituitary tumor. A weak TSH response in the TRH test, elevated sex hormone binding globulin (SHBG) levels, and the absence of a family medical history of SITSH or TRβ gene mutations supported the diagnosis of TSH-secreting pituitary adenoma (TSHoma). However, complete TSH suppression and a blunted cholesterol response in the T3 suppression test as well as normal glycoprotein α-subunit (α-GSU) levels were not compatible with TSHoma. Since TSH, FT3, and FT4 spontaneously returned to normal ranges after admission, he was discharged. One month after his discharge, thyrotoxicosis with elevated serum TSH levels relapsed. After admission, his serum TSH levels returned to within the normal range. After his discharge from the second admission, his serum TSH levels fluctuated in accordance with serum FT3 and FT4 levels and symptoms, such as palpitations. Ten months after his discharge, he was admitted to our department again due to adrenal insufficiency and thyrotoxicosis with elevated serum TSH levels, suggesting cyclic SITSH. Alth...
Source: Endocrine Journal - Category: Endocrinology Tags: Endocr J Source Type: research