Inappropriate secretion of thyroid stimulating hormone in a Filipino patient with a pituitary macroadenoma.

Pituitary tumors producing thyrotropin are very rare. We report a case of a 38-year-old, male admitted for seizure, preceded by 1 week history of generalized weakness, fatigue, anorexia, nausea and vomiting, with a 5 year history of recurrent headache followed by blurring of vision, who was found to have persistently elevated serum free thyroid hormones and non-suppressed thyroid stimulating hormone (TSH) levels, with tumor residual after craniotomy with excision of the pituitary macroadenoma. To our knowledge, this is the first reported case of TSH-producing adenoma in the Philippines.