Complications
Hypothyroidism carries serious physical and mental risks for all ages. Studies indicate that subtle adverse health effects occur even with subclinical hypothyroidism, a condition in which the patient has no symptoms but blood tests indicate hypothyroidism. Fortunately, hypothyroidism is now easily diagnosed, and treatment will restore normal thyroid function and relieve symptoms and physical signs of the disease. With treatment, a patient should expect to live a normal life, free of harmful consequences. It should be noted, however, that iodine deficiency and goiter are still major problems in less developed nations, causing varying degrees of mental retardation in millions of people.
Emergency Conditions
Myxedema Coma. Myxedema coma is a rare, life-threatening complication of untreated hypothyroidism. Symptoms include a severe drop in body temperature (hypothermia), delirium, reduced lung function, slow heart rate, constipation, urine retention, seizures, stupor, fluid build-up, and finally coma. It is uncommon, but may develop in untreated patients subjected to severe stress, such as infection, surgery, or extreme cold. Certain drugs (such as sedatives, pain killers, narcotics, amiodarone, and lithium) may increase the risk. Emergency treatment is required. Mortality rates are high (between 30 - 60%) with the highest risks in older patients and those with persistent hypothermia or heart problems.
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Suppurative Thyroiditis. Suppurative thyroiditis is a life-threatening infection of the thyroid gland. It is very rare, since the thyroid is normally immune to infection. People with pre-existing thyroid diseases, such as Hashimoto's thyroiditis, however, may be at higher than average risk for it. It often begins with an upper respiratory infection. Symptoms include fever, neck pain and rash, and trouble swallowing and speaking. Immediate treatment is critical.