Graves Disease

Graves disease is an autoimmune disorder and the most common cause of hyperthyroidism. TSH-receptor antibodies (TRAb), also called thyroid-stimulating immunoglobulins (TSI), bind to and switch on the TSH receptor of thyroid cells. Pituitary feedback cannot turn these antibodies off, so the gland enlarges diffusely (goitre) and keeps producing excess T4 and T3. Excess thyroid hormone speeds metabolism and heightens the body's response to adrenergic stimulation. The typical picture is heat intolerance, sweating, weight loss despite a good appetite, tremor, anxiety, restlessness, muscle weakness, fatigue and a rapid pulse. About 1 in 3 people with Graves disease develop thyroid eye disease. In about 85% of cases it begins within 18 months before or after the onset of hyperthyroidism, so it can appear before the thyroid problem is diagnosed. The same autoimmune process inflames and swells the muscles and fatty tissue behind the eyeball. This produces gritty or dry eyes, forward bulging of the eyes (proptosis) and double vision, and in severe disease lids that cannot close, changes in colour vision or loss of part of the visual field. Some patients develop...