Adrenal Insufficiency Test

Adrenal insufficiency is an endocrine disorder where the adrenal glands situated above the kidneys stop to produce substantial amount of steroid hormones, mainly cortisol and it may also affect the aldosterone production. Broadly, there are two types of adrenal insufficiency namely primary and secondary adrenal insufficiency. Primary adrenal insufficiency can be further classified under three categories, one type of which is called idiopathic insufficiency, which is caused due to an unknown reason. The second subtype is caused due to Addison's disease or autoimmune adrenalitis which is an autoimmune disease and other causes include tumor of the adrenal gland. Secondary adrenal deficiency is a result of damaged hypothalamus or pituitary gland. There third, not so significant, type is the tertiary adrenal insufficiency which is caused due to a hypothalamic disease. Adrenal insufficiency test includes a few laboratory tests, to assess the health condition.

Symptoms of Adrenal Insufficiency

It has been observed that the symptoms are somewhat similar to that of hypoglycemia and the affected person experiences the following conditions.

• Chronic fatigue
• Loss of appetite
• Muscle weakness
• Weight loss
• Diarrhea
• Low blood sugar/Hypoglycemia
• Nausea
• Irritability
• Dizziness
• Depression
• Headache
• Perspiration

Besides the above mentioned symptoms, women tend to experience absent or irregular menstrual periods and darkening of skin can appear in case of Addison's disease.

Adrenal Insufficiency Diagnosis

The diagnosis is not as simple as it may seem. The symptoms mentioned here progress at a very slow rate and the person tends to ignore it assuming that it does not require much attention. Eventually when these symptoms become more obvious and serious, is when people seek medical help. If ignored again it could lead to adrenal crisis, wherein symptoms are more severe and it includes sudden severe pain in the abdomen, lower back and in the legs. Low blood pressure, dehydration and losing consciousness are also some of the symptoms related to adrenal crisis.

Diagnostic Test for Adrenal Insufficiency

Although analysis is difficult to perform, there are certain tests that can be performed to determine adrenal inadequacy and the causes of it. Before advising to conduct the various laboratory tests, the doctor reviews the history of the patient and the symptoms that are visible in the patient. Once the doctor establishes the relationship of the symptoms with deficiency of adrenal hormone, s/he performs the following tests. These tests are mainly performed to check the cortisol levels and to establish the cause of insufficient cortisol levels, if any.

ACTH Stimulation Test: The most common test is the ACTH stimulation test. In this test, an artificial form of ACTH is injected and before and after giving this injection, the levels of blood and urine cortisol are measured. While normally in a person who is not affected, there will be a rise in the levels of blood and urine cortisol, those with adrenal insufficiency will have a slight or no rise in the blood and urine cortisol levels.

CRH Stimulation Test: If the result of ACTH test is negative, a CRH stimulation test is conducted by the endocrinologists to determine the cause of low blood and urine cortisol levels. In this diagnostic test, an artificial CRH is injected in the veins and the blood cortisol is measured at different intervals before and after the injection. While those with Addison's disease produce no cortisol but, high levels of ACTH, those with secondary adrenal insufficiency have a late or no reaction to the ACTH. No ACTH response indicates that the pituitary gland is damaged and a late ACTH response indicates the cause to be hypothalamus.

ACTH and CRH stimulation tests are the two major tests that help to identify the levels of cortisol. The treatment mainly involves replacing the hormones that are not being formed by the adrenal glands. An artificial glucocorticoid, such as prednisone, hydrocortisone or dexamethasone is used as a substitute for cortisol. This is done through oral medication. If aldosterone is also found to be deficient then, it is substituted with fludrocortisone acetate or florinef by taking it orally.