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The adrenal glands can be evaluated in several different ways and more than one of these may be required to fully understand the nature of the problem. Conventional physicians routinely test for adrenal function by measuring the levels of the adrenal hormone cortisol.
Function
Because cortisol is secreted at different levels throughout the day (most in the morning, least around midnight), multiple samples (usually 4) should be taken through out the day at specific times. Individual samples can be taken by blood or saliva. A single serum or saliva cortisol by itself will usually not be very useful.
Alternatively, a 24-hour cumulative urine test can be done which will show how much cortisol was secreted during that period. This test, while very useful, does not reveal any information about the adrenal output at any specific time.
An ACTH (Cortrosyn) baseline and challenge may be the best tests to determine whether your adrenal glands are able to respond to signals from your brain. The pituitary may not be producing enough ACTH or - more likely - the adrenal glands may not be responding adequately to the brain's signals. Some consider two 24-hour urine samples, one before and one after the ACTH injection, to be the best method of testing for adrenal weakness.
The dexamethasone test, along with baseline measurements, is usually performed only when adrenal hyperfunction is being evaluated. It can differentiate adrenal disease (altered response to ACTH ) from pituitary disorders (altered production of ACTH).
The secretion of ACTH from the pituitary gland is normally regulated by the level of cortisol in the blood. ACTH stimulates the adrenal cortex to produce cortisol. As plasma cortisol levels increase, ACTH secretion is suppressed; as cortisol levels decrease, ACTH increases. Dexamethasone is a synthetic steroid similar to cortisol, which suppresses ACTH secretion in normal individuals. Giving dexamethasone should reduce ACTH levels resulting in decreased cortisol levels.
Expected Outcome
With or without lab testing, if symptoms indicate adrenocortical deficiency, a low dose therapeutic trial of cortisol for several weeks may prove both informative and helpful.
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Test Adrenal Function can help with the following: | | | | | Hormones |  Low Adrenal Function / Adrenal Insufficiency | Adrenal function can be evaluated in several ways by blood, saliva, and/or urine testing. Your doctor should know the best test to use depending on the suspected severity of the condition. |
Cushing's Syndrome / Hypercortisolism| | A 24-Hour urinary free cortisol level is the most specific diagnostic test. Levels higher than 50 to 100mcg per day for an adult suggest Cushing's syndrome. Once Cushing's syndrome has been diagnosed, other tests are used to find the exact location of the abnormality that leads to excess cortisol production. These tests could include dexamethasone suppression test, CRH stimulation test, direct visualization of the endocrine glands (radiologic imaging), petrosal sinus sampling and the dexamethasone-CRH test. |
 Hypothyroidism |
Immunity |
Chronic Fatigue / Fibromyalgia Syndrome |
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KEY | | May do some good | | | Highly recommended |
GLOSSARY
Adrenal (Adrenal Gland, Adrenal Glands, Adrenals)
The adrenal glands sit on top of each kidney and consist of an outer cortex and an inner medulla. Of the 50 or so hormones the adrenals make, only cortisone and adrenaline are recognized by most people. Some of these hormones must be produced to preserve life, while others help resist stress. Other hormones from the adrenals control normal energy output (along with the thyroid) and govern the breakdown of stored energy into quick energy sources. The medulla produces epinephrine and norepinephrine, which are specifically designed to help the body deal with stressful situations. The adrenals control the body's potassium/sodium balance, which is vital for energy production. They also produce sex hormones in minute amounts, which is important for later years when the gonads drop or cease their production.
Cortisol
A hormone. Its most important function is to help the body respond to stress. It also helps regulate your body's use of protein, carbohydrates and fat; it helps maintain blood pressure and cardiovascular function; it stems inflammation.
DHEA (DHEA-S)
Dehydroepiandrosterone (DHEA) is a steroid produced by the adrenal glands and is the most abundant one found in humans. DHEA may be transformed into testosterone, estrogen or other steroids. It is found in the body as DHEA or in the sulfated form known as DHEA-S. One form is converted into the other as needed.
Gland (Glands)
The glandular system is one of the most important and complicated systems of the body. Gland tissue can be either an organ or general tissue that secretes chemicals and there are two types of gland: exocrine and endocrine. Those glands which secrete chemicals through tubules or ducts are called exocrine and include sweat, tear and salivary glands. Ductless glands - part of the endocrine system - secrete special chemicals (hormones) directly into the blood.
Hormones (Hormone)
Chemical substances secreted by a variety of body organs that are carried by the bloodstream and usually influence cells some distance from the source of production. Hormones signal certain enzymes to perform their functions and, in this way, regulate such body functions as blood sugar levels, insulin levels, the menstrual cycle, and growth. These can be prescription, over-the-counter, synthetic or natural agents. Examples include adrenal hormones such as corticosteroids and aldosterone; glucagon, growth hormone, insulin, testosterone, estrogens, progestins, progesterone, DHEA, melatonin, and thyroid hormones such as thyroxine and calcitonin.
Immune System (Immune Response, Immunity)
A complex that protects the body from disease organisms and other foreign bodies. The system includes the humoral immune response and the cell-mediated response. The immune system also protects the body from invasion by making local barriers and inflammation. The process may involve acquired immunity (the ability to learn and remember a specific infectious agent), or innate immunity (the genetically programmed system of responses that attack, digest, remove, and initiate inflammation and tissue healing).
Microgram (mcg, Micrograms, ug)
0.000001 or a millionth of a gram.
Saliva (Salivary)
The watery mixture of secretions from the salivary and oral mucous glands that lubricates chewed food and moistens the oral walls.
Serum
The cell-free fluid of the bloodstream. It appears in a test tube after the blood clots and is often used in expressions relating to the levels of certain compounds in the blood stream.
Sinuses (Sinus)
Four pairs of air pockets lined with membranes in the bones around the nose. The ethmoid sinuses are located on each side of the nose between the eyes; the maxillary sinuses are located in the cheek above the teeth and below the eyes; the sphenoid sinuses are located deeply behind the eyes; the frontal sinuses are located in the forehead.
Steroid (Steroids)
Any of a large number of hormonal substances with a similar basic chemical structure containing a 17-carbon 14-ring system and including the sterols and various hormones and glycosides.
Syndrome
A medical condition characterized by a collection of related symptoms (what the patient feels) and signs (what a doctor can observe or measure).
Thyroiditis (Chronic Thyroiditis, Hashimoto's Thyroiditis)
Inflammation of the thyroid; there are several forms of thyroiditis, including chronic or Hashimoto's thyroiditis (also called autoimmune or chronic lymphocyctic thyroiditis), subacute thyroiditis, and painless or postpartum thyroiditis. Thyroiditis often results in hypothyroidism.
Last updated: Jul 12, 2008
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