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Graves' Disease

Graves' disease is an autoimmune disorder caused by immunoglobulin antibodies that bind to TSH receptors and initiate production and release of thyroid hormone. Graves' disease is the most common cause of hyperthyroidism. As is true with most autoimmune diseases of the thyroid, Graves' disease is more prevalent in women. In addition to symptoms of hyperthyroidism, 50 percent of patients with Graves' disease also exhibit exophthalmos.

Evaluation and Diagnosis. When ophthalmopathy accompanies the cardinal signs of hyperthyroidism, Graves' disease should be suspected. Elderly patients may also present with fatigue, a symptom not seen in younger patients.

Treatment. Three approaches are available for treating Graves' disease (Table 9): surgical excision of the thyroid, thyroid-suppressive drugs, and radioactive ablation of the thyroid gland. In addition, beta blockers can be used to control symptoms of thyrotoxicosis until the cause of hyperthyroidism is established and treated.

Surgery is reserved for individuals in whom medication or radioactive iodine ablation are not acceptable options, or when a large goiter is present that compresses nearby structures or is disfiguring.

Antithyroid drugs are well tolerated and effective in blocking the production and release of thyroid hormone in patients with Graves' disease. These drugs work by blocking the organification of iodine. PTU also prevents peripheral conversion of T4 to the more active T3. PTU must be given in divided doses two or three times per day, whereas methimazole can be administered once per day.

Ablation with radioactive iodine is

Treatment of Graves' Disease

Treatment Adult dosage Indications Side effects Contraindications

Symptomatic relief

Propranolol 40 to 160 mg Tachycardia Wheezing, lethargy, Asthma, congestive

(Inderal)per day depressed cardiac heart failure function

Verapamil 240 to 360 mg Tachycardia Constipation, Congestive heart

(Calan, Isoptin) per day depressed cardiac failure, heart block,

function hypotension

Thyroid suppression

Propylthiouracil (PTU) 100 to 600 mg Rash, itching, None listed

per day (especially in arthralgias, hepatic

children) dysfunction,

PTU preferred agranulocytosis

in pregnancy

Methimazole I 0 to 40 mg None listed

(Tapazole) per day

Thyroid ablation

Radioactive iodine Variable Nonpregnant Hypothyroidism Pregnancy, breast-

adult feeding

Surgery Pregnant woman Hypothyroidism, None listed

unable to take hypoparathyroidism, oral therapies, inadvertent injury to recurrent laryngeal

with thyroid nerve

The treatment of choice for Graves' disease in older patients. Radioactive iodine should not be used in children, pregnant women, or nursing mothers. In addition, there is a possibility that using radioactive iodine in patients with active ophthalmopathy may accelerate progression of eye disease. For this reason, some experts initially treat Graves' disease with oral suppressive therapy until ophthalmopathy.

Treatment of thyroid storm is important for patients with symptomatic Graves' disease. Administration of high doses of PTU I100 mg every six hours) to quickly block thyroid release and reduce peripheral conversion of T4.