Myxedema

Severe hypothyroidism characterized by generalized nonpitting, mucopolysaccharide-rich dermal and subcutaneous edema, classically involving the face and extremities, and accompanied by marked slowing of metabolic processes and potential progression to myxedema coma. Possible causes for hypothyroidism are autoimmune Hashimoto's thyroiditis, thyroidectomy, radiotherapy, medications (lithium, amiodarone), and pituitary/hypothalamic failure. Common triggers of myxedema coma in patients with undiagnosed or poorly managed hypothyroidism are infection, exposure to cold, medications (sedatives, narcotics, anesthesia), trauma, and surgery.