Children who present with thyrotoxicosis have symptoms of nervousness, palpitations, weight loss, muscle weakness, and fatigue. A history of developmental delay and declining school performance may be found.9 Other symptoms include tremulousness, anxiety, excessive sweating, temperature intolerance, and emotional lability. Gastrointestinal overactivity with symptoms of frequent stools is common. An increased appetite is classically present. However, an apathetic state, including decreased appetite, occasionally occurs.
The signs of Graves' disease are similar to those seen in adults but the ophthalmologic signs are usually milder in children.10,11 Signs of sympathetic and cardiac overactivity are common. These include tremor, brisk deep tendon reflexes, tachycardia, supraventricular tachycardia, flow murmur, overactive precordium, and a widened pulse pressure. Other cardiac atrioventricular conduction disturbances may occur, such as atrial fibrillation, atrioventricular block, or sinoatrial block. CHF may develop because of the inability of cardiac function to meet metabolic demands and papillary muscle dysfunction, causing mitral valve prolapse, may occur.12,13 Except in neonates and children with underlying cardiac disease, CHF is uncommon in childhood thyrotoxicosis. In thyroid storm, severe hyperpyrexia, atrial dysrhythmia and CHF, delirium or psychosis, severe gastrointestinal hyperactivity, and hepatic dysfunction with jaundice are present.14 A history of a precipitating event, illness, or major stress, should be identified.