Diagnosing adrenal insufficiency, particularly in its early stages, can be challenging. A thorough review of the patient’s medical history and symptoms may raise suspicion of Addison’s disease. Laboratory tests are then employed to confirm the diagnosis and determine its underlying cause. Imaging studies of the adrenal and pituitary glands are also valuable in establishing the cause.
The ACTH stimulation test is widely used for diagnosing adrenal insufficiency. It involves measuring blood cortisol levels before and after administering synthetic ACTH via injection. A normal response entails a rise in cortisol levels, whereas individuals with Addison’s disease or long-standing secondary adrenal insufficiency typically show little to no increase in cortisol levels. Low- and high-dose ACTH stimulation tests may be utilized based on the suspected cause of adrenal insufficiency.
In cases where the ACTH test yields abnormal results, a CRH stimulation test can help identify the cause. This test involves administering synthetic CRH intravenously and monitoring blood cortisol levels before and after the injection. The response pattern aids in distinguishing between Addison’s disease and secondary adrenal insufficiency, with specific abnormalities indicating the involvement of the pituitary or hypothalamus.
During an Addisonian crisis, immediate treatment with salt, glucose-containing fluids, and glucocorticoid hormones is essential. While a definitive diagnosis may not be feasible during crisis management, preliminary diagnosis can be based on blood ACTH and cortisol levels measured before administering glucocorticoids. Additional tests, including radiologic studies and blood tests for specific antibodies, may be conducted once Addison’s disease is confirmed.
For secondary adrenal insufficiency, imaging techniques such as CT scans are employed to assess the size and structure of the pituitary gland. These diagnostic approaches help tailor treatment strategies and provide valuable insights into the underlying pathology.