Very low thyroid function causes which condition?

• A. Myxedema
• B. Graves' disease
• C. Addison's disease
• D. Cushing's syndrome

Answer: (A)

Very low thyroid function, or hypothyroidism, leads to a buildup of mucopolysaccharides in the skin and other tissues, causing edema and the characteristic appearance called myxedema. In its more severe form, hypothyroidism can progress to myxedema coma if untreated. Graves' disease, by contrast, is an autoimmune form of hyperthyroidism with symptoms like weight loss, heat sensitivity, rapid heartbeat, and often eye changes. Addison's disease is adrenal insufficiency, presenting with fatigue, low blood pressure, hyperpigmentation, and electrolyte disturbances. Cushing's syndrome is from excess cortisol, causing features like centralized weight gain, moon face, and purple striae. So very low thyroid function is associated with myxedema.