How is Addison’s disease and an acute adrenal crisis diagnosed?

How is Addison’s disease and an acute adrenal crisis diagnosed?

How is Addison’s disease diagnosed?

It is likely that your doctor will first ask you about your medical history and then conduct a physical examination to look for any symptoms and signs. If it is suspected that you are at risk or have Addison’s disease, then your doctor will suggest that you undergo one or a few of the below tests:

  • Blood test – A blood test is conducted in order for your doctor to measure the levels of sodium, potassium, ACTH and cortisol in your blood. These results will give an indication as to whether your adrenal glands are working properly (to check for adrenal insufficiency) and if this issue is the cause of your symptoms. It is also possible for a blood test to measure antibodies that are associated with other autoimmune disorders and Addison’s disease.

**My Med Memo -  For a blood test to be conducted your doctor will take a sample of your blood, which is normally extracted from a vein in your arm using a needle, or via a simple finger prick. The blood test sample will then be sent to a lab for testing where lab workers will analyse it. Your results will be available within 24 hours for a simple blood test, however, you may have to wait longer depending on what you are being tested for. Your doctor will phone you once he or she has obtained the results.

  • ACTH (adrenocorticotropic hormone) stimulation test / synacthen stimulation test –ACTH stimulates the production of cortisol. This test will determine how well the adrenal glands respond to ACTH. Your doctor will measure the cortisol levels in your blood before injecting you with the synthetic ACTH and after you have been injected, your cortisol levels will be measured again. If there is any damage present in the adrenal glands then the ACTH stimulation test will show that the output of cortisol levels as non-existent or limited as a result of the synthetic ACTH injection.
  • Insulin-induced hypoglycaemia test – Your doctor may suggest this kind of test if he or she thinks that pituitary disease is the possible cause of your adrenal insufficiency, this is known as secondary adrenal insufficiency. This kind of tests will involve a blood test to check for the presence of glucose (sugar) in the blood, as well as the cortisol levels at a number of different intervals after you have been injected with insulin. Insulin is a hormone that aids in regulating the glucose in your body. If you are healthy, your glucose levels will fall as the insulin comes into effect and your cortisol levels should rise as a physiological stress response to the extremely low glucose levels. If cortisol levels don't rise with hypoglycemia then adrenal insufficiency is present.
  • Imaging tests – You may have to have a CT scan (computerized tomography) conducted. This form of imaging test uses a combination of X-ray images that are taken from a number of different angles (cross-sectional) which will allow for your doctor to get a view of your internal organs and detect any abnormalities. In the case of an Addison’s disease diagnosis, your doctor will conduct a CT scan of your abdominal area to look at the size of the adrenal glands and if they appear abnormal in any way. You may also have to undergo an MRI scan (magnetic resonance imaging). This test will scan your pituitary gland if your doctor suspects you have secondary adrenal insufficiency. An MRI scan uses radio waves to create images of your internal organs. Thyroid function test - This test will determine whether your thyroid is functioning correctly. The thyroid gland is located in the neck and produces a number of hormones that aid in controlling your metabolism and body growth. Those who suffer from Addison’s disease are often diagnosed with hypothyroidism, this is an underactive thyroid. Your hormone specialist, known as an endocrinologist, will test the levels of specific hormones using blood tests and determine whether or not your thyroid is the cause of any of your symptoms.

Diagnosing acute adrenal crisis

When Addison’s disease is not treated, it will eventually lead to an acute adrenal crisis, meaning that the symptoms of Addison’s disease occur rapidly, as well as severely.

During this crisis, there will not be any time for a synacthen stimulation test to be performed to confirm that Addison’s disease is the cause. If it is possible, then your doctor may take a sample of your blood in order for it to be tested for abnormalities. An ACTH stimulation test will only be performed when the crisis has been controlled through steroid injections, as well as the administration of fluids that contain glucose and salt.

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