Occult T3 toxicosis in McCune-Albright syndrome.

We report a girl with McCune-Albright syndrome who presented with Cushing syndrome from adrenal hypersecretion and gonadotrophin-independent precocious puberty in the first year of life. At age 5, she failed to gain weight and was found to have hyperthyroidism, which was occult in that she had T3 toxicosis without a goitre or thyroid ultrasound abnormality. The latter has not been previously reported in McCune-Albright syndrome.