TSH-secreting pituitary macroadenoma in an 11-year-old girl.

Graves' disease, multinodular toxic goiter or toxic adenoma are the usual causes of hyperthyroidism in children as well as in adults. We report a case of hyperthyroidism due to TSH-secreting pituitary macroadenoma in an 11-year-old girl. The patient was admitted to the Endocrine Department for pituitary function evaluation, five months after transfrontal adenomectomy and pituitary irradiation for a macroadenoma. On admission the patient was clinically hyperthyroid and the work-up established a diagnosis of hyperthyroidism due to TSH-secreting adenoma (high levels of TSH in the face of hyperthyroidism, no TSH response to TRH stimulation, diffuse thyroid goiter without eye signs or pretibial myxedema). Of interest in this case was the fact that: (a) she is the youngest patient reported with hyperthyroidism due to a TSH-secreting macroadenoma and (b) hyperthyroidism was diagnosed after adenomectomy.