Adrenal exhaustion is also known by the medical term "adrenal insufficiency." It can be due to a variety of causes, ranging from autoimmune to infectious to drug-induced conditions. It can be quite dangerous, and the symptoms can place considerable burden on the lives of those affected. The main hormones affected are ACTH (adrenocorticotropic hormone), which is released by the pituitary and causes release of mineralocorticoid and cortisol (whose levels are also affected) from the adrenal glands. The problem can reside in the pituitary gland or in the adrenals. A number of symptoms may present clinically as a result of deficiency of these hormones.
Nonspecific Complaints
Nonspecific complaints, which are general symptoms that can occur with many other syndromes as well, include fatigue, weakness and weight loss. Weakness and fatigue occur almost universally in patients with adrenal insufficiency.
Gastrointestinal Symptoms
Nausea and vomiting, constipation, abdominal pain and diarrhea occur commonly with adrenal insufficiency. These symptoms may have a variety of causes; one example is associated electrolyte disturbances.
Dizziness
Dizziness is a common side effect and is marked when the patient stands up. Dizziness when standing up, called orthostatic hypotension, can result from decreased volume in the blood vessels because of the lack of mineralocorticoid. Mineralocorticoids normally function to retain salt and water via action at the level of the kidney.
Low Blood Sugar
Low blood sugar can contribute to the malaise and fatigue felt by most patients. It results from the lack of cortisol, a stress hormone that mobilizes blood sugar in times of need.
Electrolyte Disturbances
Increased potassium and decreased sodium are common in patients with adrenal insufficiency. Mineralocorticoid works by increasing sodium reabsorption and potassium/acid excretion at the level of the kidney. Deficiency results in predicted abnormalities and can be dangerous, as high potassium can have toxic effects on the heart and low sodium can affect the nervous system in the form of seizures or altered mental status. Muscle pain and weakness can also result from the increased potassium, and usually the body is in a state of acidosis from unexcreted acidic ions.
Decreased Androgens
Androgens are also released from the adrenals in response to ACTH release. When there is no stimulus for release, a variety of symptoms can occur in males and females due to decreased androgen levels. Males can suffer from small testes, changes in libido and even impotence. Women will tend to have decreased axillary and pubic hair.
Hyperpigmentation
Hyperpigmentation, or darkened skin color, is an interesting finding that occurs only when the problem causing adrenal insufficiency resides with the adrenal glands. Due to low mineralocorticoid and cortisol levels from the adrenals, the pituitary releases more and more ACTH in an attempt to "jump-start" the adrenals, usually to no avail. Interestingly, ACTH also has an effect on melanocytes, which are cells responsible for skin pigmentation (found in the skin and gums), and the increased ACTH from the pituitary results in increased pigment production by the melanocytes.
Adrenal Crisis
Adrenal crisis is an acute presentation of adrenal insufficiency that basically manifests as hypotension (low blood pressure) and collapse of the circulatory system. Abdominal pain is usually present, as are fever and lab abnormalities like increased potassium, decreased sodium and decreased blood sugar. This is a life-threatening emergency and must be evaluated and treated with urgency.
References
- "Williams Textbook of Endocrinology, 11th Edition;" H.M. Kronenberg; 2008
- "The Osler Medical Handbook, 2nd Edition;" J.P. Piccini and K.R. Nilsson; 2006
- "Journal of Clinical Endocrinology and Metabolism;" Clinical, Immunological, and Genetic Features . . . ; M. Erichsen et al.; December 2009
