Abstract.Urinary N-acetyl-ƒÀ-

A 24-year-old man showed thyrotoxic symptoms with hypokalemic periodic paralysis. Serum thyroid hormone levels were high and thyrotropin (TSH) was undetectable. 123I-thyroidal uptake was suppressed. TSH-binding inhibitor immunoglobulin (TBII) was positive. After a month without any treatment, he became hypothyroid. Thyroid hormone level was decreased and TSHwas increased to above the normal range. 123I-thyroidal uptake was increased. TBII activity was still positive. From the clinical findings, a diagnosis of silent thyroiditis was made. Sera obtained in the hypothyroid state revealed the presence of thyroid-stimulationblocking antibodies (TSBAb), but there were no thyroid-stimulating antibodies (TSAb). These results suggest that the hypothyroidism in this patient was due to the presence of TSBAbwith TBII activity.

Abstract. A 42-year-old female with Graves' disease and papillary thyroid carcinoma with lung metastasis was referred to our hospital. After treatment of thyrotoxicosis with methimazole and Lugol's solution, she underwent total thyroidectomy. She was then given 131I twice to treat lung metastasis. However, 131I uptake into the lung was not clear in the scintigram. Both thyroid-stimulating antibodies (TSAb) and thyroid-stimulation-blocking antibodies (TSBAb) were detected in her sera before and after the treatments. Compared with TSAb activities, TSBAb activities were extremely high. Changes in the titers of these two antibodies were not clear after total thyroidectomy. These results indicate that lymphocytes outside the thyroid gland are the major source of TSAb and TSBAb in this patient.

A 63-year-old housewife with a history of partial thyroidectomy was referred to our hospital because of a neck mass and abdominal tumor. Aspiration biopsy of the neck tumor revealed the recurrence of papillary thyroid carcinoma. Magnetic resonance imaging (MRI) of the abdomen and urinary and plasma catecholamine levels indicated that the tumor beside the abdominal aorta was an extraadrenal pheochromocytoma. Two tumors were excised and histologic studies confirmed the diagnosis. So far two cases of extraadrenal pheochromocytoma with papillary thyroid carcinoma have been reported. The present case indicates that the presence of papillary thyroid carcinoma should be considered in patients with extraadrenal pheochromocytoma.