Final answer:
The initial test for Addison's disease involves measuring cortisol and adrenocorticotropic hormone (ACTH) levels in the blood. If Addison's is suspected, antibodies to enzymes like the 21-hydroxylase can be diagnostic for autoimmune Addison Disease.
Step-by-step explanation:
Initial Test for Addison's Disease
The first test for diagnosing Addison's disease, also known as primary adrenal insufficiency (PAI), typically involves measuring blood levels of cortisol and adrenocorticotropic hormone (ACTH). In Addison's disease, there is a hyposecretion of cortisol due to the destruction of the adrenal glands. This is often an autoimmune process where the body's immune system mistakenly attacks the adrenal cortex. The measurement of ACTH can help determine whether the condition is due to a primary adrenal failure or a deficiency in ACTH production by the pituitary gland.
Additionally, patients with autoimmune Addison Disease (AAD) often have antibodies to enzymes like the 21-hydroxylase (21-OH), which are diagnostic for the condition. This autoimmune response may also be associated with conditions like autoimmune polyendocrine syndromes (APS), involving other endocrine glands.
If blood tests suggest Addison's disease, further testing, such as the corticotropin-releasing hormone stimulation test, may be performed. Treatment involves life-long cortisol replacement therapy.