WHAT'S SO 'HOT' ABOUT RADIOACTIVE IODINE? : FELINE HYPERTHYROIDISM TREATMENT OPTIONS

摘要

Feline hyperthyroidism (thyrotoxicosis) is the most common endocrinopathy in cats. It was first diagnosed in the late 1970s and has had an increased frequency in diagnosis due to: increased clinical awareness of the disease, increased improvement in diagnostic testing, increased feline population, the increased lifespan of pet cats and an increase in owner interest in seeking veterinary care. Thyrotoxicosis results from the excess secretion of the thyroid hormones. Thyroid hormones are the only iodinated organic compounds in the body. The only function for ingested iodine is for thyroid hormone synthesis. Ingested stable iodine is converted to iodide in the GI tract and is then absorbed into the circulation. Iodide is either concentrated or trappedby the active transport mechanism of the thyroid follicular cell. In the thyroid gland-iodide is oxidized to iodine- triiodothyronine (T3) and thyroxine (T4). These hormones are produced by multinodular adenomas (which appear as small, grape-like nodulesthat spread throughout the thyroid gland), adenomatous hyperplasia (large, solitary, non-encapsulated masses) or thyroid carcinomas (rarely seen in cats).