Diagnosis
If the person is in adrenal crisis, the ACTH stimulation test may be given. If not in crisis, cortisol, ACTH, aldosterone, renin, potassium and sodium are tested from a blood sample before the decision is made if the ACTH stimulation test needs to be performed. X-rays or CT of the adrenals may also be done. The best test for adrenal insufficiency of autoimmune origin, representing more than ninety percent of all cases in a Western population, is measurement of 21-hydroxylase autoantibodies.
| Source of pathology | CRH | ACTH | DHEA | DHEA-S | cortisol | aldosterone | renin | Na | K | Causes5 |
| hypothalamus (tertiary)1 |
low | low | low | low | low3 | low | low | low | low | tumor of the hypothalamus (adenoma), antibodies, environment (i.e. toxins), head injury |
| pituitary (secondary) |
high2 | low | low | low | low3 | low | low | low | low | tumor of the pituitary (adenoma), antibodies, environment, head injury, surgical removal6, Sheehan's syndrome |
| adrenal glands (primary)7 |
high | high | high | high | low4 | low | high | low | high | tumor of the adrenal (adenoma), stress, antibodies, environment, Addison's Disease, trauma, surgical removal (resection), miliary tuberculosis of the adrenal |
| 1 | Automatically includes diagnosis of secondary (hypopituitarism) |
| 2 | Only if CRH production in the hypothalamus is intact |
| 3 | Value doubles or more in stimulation |
| 4 | Value less than doubles in stimulation |
| 5 | Most common, does not include all possible causes |
| 6 | Usually because of very large tumor (macroadenoma) |
| 7 | Includes Addison's disease |
Read more about this topic: Adrenal Insufficiency