letter and Hypothyroidism

A thirteen-year-old girl was admitted complaining of short stature and anemia. The low titers of her serum T3 and T4 and the abnormally high TSH level represented primary hypothyroidism. Although she had normal sellar size, CT demonstrated an intra- and suprasellar round mass with homogeneous enhancement. With thyroid replacement therapy the enhanced mass diminished on CT within 5 months, and her symptoms regressed. Twelve cases with radiological diminution of pituitary mass or visual field improvement after thyroid replacement therapy are reviewed. They were considered to be pituitary hyperplasia, rather than pituitary adenoma, caused by long-standing untreated hypothyroidism. In four of them, the pituitary mass on CT was diminished after the therapy. Characteristic CT findings of pituitary hyperplasia, including our case, was a round isodensity mass with homogeneous enhancement in the midline of the pituitary region. In the experimental studies, pituitary hyperplasia is based on the feedback mechanism of hypothalamic-pituitary-thyroid axis, and ultimately autonomous pituitary adenoma may occur. Pituitary mass with hypothyroidism, visual field defect, amenorrhea or galactorrhea tend to be mistaken for prolactinoma or non-functioning adenoma with pituitary hypothyroidism. Thorough endocrinological examination must be carried out. The first choice of treatment for this type of pituitary mass should be thyroid replacement therapy. If there is no improvement of visual field, no regression of pituitary mass on CT, or continuing high TSH levels, then pituitary surgery must be considered.

Topics: Adolescent; Female; Humans; Hyperplasia; Hypothyroidism; Pituitary Gland; Thyroid (USP); Tomography, X-Ray Computed

A 21-year-old woman was referred because of abdominal pain. On physical examination, her abdomen was distended up to the umbilical region. Ultrasound and computer tomography of the abdomen revealed bilateral multiple ovarian cysts. Laboratory studies revealed increased liver function, total cholesterol and creatine phosphokinase. Further clinical investigations determined that the patient suffered from primary hypothyroidism due to autoimmune thyroiditis. The cysts resolved spontaneously after the simple replacement of a thyroid hormone. Some reports have been published of primary hypothyroidism presenting as ovarian cysts and precocious puberty in prepubertal girls. However, the case presented herein indicates that an ovarian tumor as a result of hypothyroidism may also occur in adult females. To avoid inadvertent surgery to remove an ovarian tumor, it is essential that a patient with multiple ovarian cysts and hypothyroidism be properly managed, as the simple replacement of a thyroid hormone could resolve the ovarian cysts.

Topics: Diagnosis, Differential; Female; Hormone Replacement Therapy; Humans; Hypothyroidism; Ovarian Cysts; Thyroid (USP); Young Adult

A case of Plummer's disease that spontaneously progressed to hypothyroidism is presented. A 49-year-old female visited our hospital because of a 3 kg decrease in body weight during the previous month and a painless nodule in the right anterior area of her neck. A diagnosis of Plummer's disease was made based on the results of thyroid function tests, thyroid scintigrams, and an ultrasonogram, but the patient's disease followed an usual clinical course. About two months later, she gradually developed manifestations of permanent hypothyroidism, and anti-thyroid autoantibodies became positive. In spite of continuous administration of levothyroxine sodium, uptake of 99mTcO4- to the nodule was unchanged or rather increased according to the consecutive thyroid scintigraphies. These results suggested that this case represented an autonomously functioning nodule with underlying silent thyroiditis and Hashimoto's disease.

Topics: Autoantibodies; Disease Progression; Female; Goiter, Nodular; Humans; Hypothyroidism; Middle Aged; Radionuclide Imaging; Radiopharmaceuticals; Sodium Pertechnetate Tc 99m; Thyroid (USP); Thyroid Gland; Thyrotropin; Thyroxine; Triiodothyronine; Ultrasonography