Graves Disease

• • Diffusely hypersecretory goiter with resultant increased levels of thyroid hormone in the blood

  • Nervousness, weight loss with increased appetite, heat intolerance, increased sweating, muscular weakness and fatigue, increased bowel frequency, polyuria, menstrual irregularities, infertility

  • Goiter, tachycardia, atrial fibrillation, warm moist skin, thyroid thrill and bruit, cardiac flow murmur, gynecomastia

  • Eye signs include:

  • -Stare

    -Lid lag

    -Exophthalmos

  • Thyroid-stimulating hormone (TSH) low or absent

  • Increased radioactive iodine uptake

  • Increased tri-iodothyronine (T3) and thyroxine (T4)

  • Abnormal T3 suppression test

  • Elevated thyroid-stimulating immunoglobulin

Epidemiology

• • 85% of all hyperthyroid cases

  • Peak age of onset is fourth decade

  • Incidence: 23 per 100,000

  • Female:male ratio of 4:1 to 5:1

  • 50% of patients show clinical signs of ophthalmopathy

  • 50% of patients have myopathy that presents as proximal muscle weakness

Symptoms and Signs

• • Nervousness, increased diaphoresis, heat intolerance, tachycardia, palpitations, fatigue, and weight loss

  • Nodular, multinodular, or diffuse goiter on physical exam

  • Flushed and staring appearance

  • Warm, thin, and moist skin

  • Fine hair

  • Possible exophthalmos

  • Pretibial myxedema

  • Vitiligo

  • Shortened Achilles reflex time

Laboratory Findings

• • Suppressed TSH

  • Elevated T3, free T4, and radioactive iodine uptake

  • Failure to suppress radioiodine uptake with exogenous T3

  • Failure of rise in TSH with thyrotropin-releasing hormone (TRH) administration

  • High thyroid-stimulating immunoglobulin level

  • Low serum cholesterol

  • Lymphocytosis

  • Occasional hypercalcemia, hypercalciuria, or glycosuria

Imaging Findings

• • Diffuse increased uptake on radioactive iodine scan

  • Thyroid US reveals an enlarged gland, with or without nodules, and high vascular flow

  • Orbital US, CT, or MRI can evaluate extraocular muscles, retrobulbar soft tissue, and optic nerve

• • Clinical manifestations may go through periods of exacerbation and remission

  • Graves disease is an autoimmune disease in which antibodies are directed against the TSH receptor

  • Pathogenesis of ocular problems in Graves disease is unclear

  • Eye complications may begin before and continue after thyroid dysfunction

Rule Out

• • Anxiety neurosis

  • Pheochromocytoma

  • Primary ophthalmopathy (eg, orbital tumors)

  • Thyrotoxicosis factitia

  • Thyroiditis

• • Complete history (including family) and physical examof the thyroid gland

  • Thyroid function tests

• • Antithyroid drugs, radioactive iodine, or thyroidectomy

  • Treatment of ocular problems of Graves disease include:

  • -Maintenance of euthyroid state

    -Protecting the eyes from light and dust

    -Elevating the bed

    -Diuretic use

    -Methylcellulose or guanethidine eye drops

    -Systemic glucocorticoids

    -Ophthalmologic surgery

Surgery

Indications

• • Very large goiter or multinodular goiter with relatively low radioactive iodine uptake

  • Thyroid nodule that may be malignant

  • Patients with ophthalmopathy

  • Pregnant patients or children

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