HYPERTHYROIDISM - CURRENT TREATMENT GUIDELINES

Hyperthyroidism is common and affects approximately 2% of women and 0. 2% of men. The most common cause of hyperthyroid is Graves' disease, a n autoimmune disorder associated with circulating immunoglobulins that bind to and stimulate the thyrotropin (TSH) receptor, resulting in su stained thyroid overactivity. Toxic nodular goitres cause hyperthyroid ism due to autonomous hyperfunctioning of localised areas of the thyro id. There are 3 recognised modalities of treatment for hyperthyroidism : antithyroid drugs, surgery and radioiodine. All are effective but no single method offers an absolute cure. Patients with Graves' disease may be prescribed antithyroid drugs over a period of 12 to 18 months w ith a view to inducing a long term remission. These drugs are also oft en given for a short period to render the patient euthyroid before def initive therapy with radioiodine or thyroidectomy. However, antithyroi d drugs will not 'cure' hyperthyroidism associated with a toxic nodula r goitre. The use of radioiodine as a first-line therapy for hyperthyr oidism is growing. It is well tolerated. with the only long term seque lae being the risk of developing radioiodine-induced hypothyroidism. R adioiodine can be used in all age groups rather than children, althoug h it should also be avoided in pregnancy and during lactation. Pregnan cy should be avoided for 4 months following its administration. Radioi odine may cause a deterioration in Graves' ophthalmopathy and corticos teroid cover may reduce the risk of this complication. The treatment o f choice for toxic nodular goitre hyperthyroidism is radioiodine. Surg ery, either subtotal or near-total thyroidectomy, has limited but spec ific roles to play in the treatment of hyperthyroidism: this approach is rarely used in patients with Graves' disease unless radioiodine has been refused or there is a large goitre causing symptoms of compressi on in the neck. The goal of surgery is to cure the underlying patholog y while leaving residual thyroid tissue to maintain postoperative euth yroidism.