Addison's disease (also known as chronic adrenal insufficiency, or hypocortisolism) is a rare endocrine disorder. It is estimated that it affects about 1 to 5 in 100,000 people. It occurs when the adrenal glands, seated above the kidneys, fail to produce enough of the hormone cortisol and, sometimes, the hormone aldosterone. Addison's disease refers specifically to primary adrenal insufficiency, in which the adrenal glands themselves malfunction; secondary adrenal insufficiency occurs when the pituitary gland does not produce enough adrenocorticotropic hormone (ACTH) to adequately stimulate the adrenal glands. A famous sufferer of Addison's Disease was President John F. Kennedy.
Signs and symptoms
Early signs
Addison's disease progresses slowly, and symptoms may not present or be noticed until some stressful illness or situation occurs. Common symptoms are:
Addisonian crisis
An illness or accident can aggravate the adrenal problems and cause an Addisonian crisis in which the symptoms include:
Untreated, an Addisonian crisis can be fatal. It is a medical emergency.
Diagnosis
In suspected cases of Addison's disease, one needs to demonstrate that adrenal hormone levels are low after appropriate stimulation with synthetic pituitary hormone. Once demonstrated, the cause of adrenal failure needs to be elucidated. The most common cause is autoimmune, and can be tested for with an assay for 21-hydroxylase antibodies. If there are no antibodies present, infectious or genetic causes should be sought. This may include imaging of the adrenal glands, tests for tuberculosis or HIV infection, and searching for metastatic cancer.
Pathophysiology
Eighty to ninety percent of cases of Addison's disease are due to autoantibodies directed against adrenal cells containing 21-hydroxylase, an enzyme involved in the production of cortisol and aldosterone. The remainder of cases are due to tuberculosis, HIV, sarcoidosis, amyloidosis, hemochromatosis, metastatic cancer to the adrenal glands, adrenal haemorrhage and congenital adrenal hypoplasia. Addison's disease can be an expression of an autoimmune polyendocrine syndrome when autoimmune reactions against other organs are also present. In APS type 1, 70% suffer from Addison's disease, while in type 2, 100% do. Through these syndromes, Addison's is associated with hypothyroidism, diabetes mellitus (type 1),vitiligo, alopecia and celiac disease.
Treatment
Treatment for Addison's disease involves replacing the missing cortisol and, if necessary, providing replacement therapy for the missing aldosterone. Caution must be exercised when the person with Addison's disease has surgery or becomes pregnant.
References
- Addison's disease: adrenal insufficiency http://www.niddk.nih.gov/health/endo/pubs/addison/addison.htm
- Addison's disease self help group http://www.adshg.org.uk
Last updated: 02-07-2005 11:40:25
Last updated: 04-25-2005 03:06:01