A rare chronic disorder in which there is shortage of the corticosteroid hormones hydrocortisone and aldosterone, which are usually produced by adrenal cortex (the outer parts of the adrenal glands, which are located on the top of the kidneys). In addition extreme amounts of the hormone ACTH are secreted by the pituitary gland (at the base of the brain) in an attempt to increase output of the corticosteroid hormones. The activity and secretion of another hormone, melanocyte stimulating hormone (MSH), also increase, which leads to increased synthesis of melanin pigment in the skin.
Addison’s disease can be caused by any disease that destroys the adrenal cortecise. Autoimmune disorder is the most the most common cause in which the immune system produces antibodies that attack the adrenal glands.
Symptoms of the disease mostly develop gradually over months or years and include weakness, tiredness, abdominal pain and weight loss. Excess MSH can cause darkening of the skin in pressure areas, the creases of palms, the body and the mouth.
Acute episodes cause Addisonian crisis brought on by injury, infection or other stresses can also occur. The symptoms of these are primarily due to Aldosterone deficiency and include extreme dehydration, muscle weakness, hypotension (low blood pressure), confusion and coma. Hypoglycaemia (low blood glucose) also occurs due to a lack of hydrocortisone.
Diagnoses and treatment
Diagnoses of Addison’s disease is usually made if the patient fails to respond to in injection of ACTH, which normally stimulates hydrocortisone secretion. To replace the deficient hormones, lifelong corticosteroid drug treatment is needed. Treatment of Addisonian crisis involves quick infusion of saline and glucose and supplementary doses of corticosteroid hormones.