Adrenal insufficiency is an endocrine disorder characterized by an inadequate production of adrenal hormones by the adrenal glands. The adrenal glands are located right above both of the kidneys and are responsible for producing the hormones aldosterone and cortisol, which have a number of critical functions in the body.
Adrenal Hormones
Aldosterone is a type of hormone called a mineralocorticoid. Aldosterone helps to maintain blood pressure and the balance of salts and fluid in the body. Cortisol is a type of hormone called a glucocorticoid. According to the National Endocrine and Metabolic Diseases Information Service, the most important function of cortisol is to help the body respond properly to stress. Cortisol helps to maintain blood pressure, cardiovascular function and blood glucose levels. Cortisol also slows immune system response and regulates metabolism of nutrients.
Types
The most common type of adrenal sufficiency is called primary adrenal insufficiency, or Addison's disease, according to the Milton S. Hershey Medical Center. This type of insufficiency occurs when an autoimmune reaction causes permanent damage to the adrenal glands. When the glands are damaged, they cannot physically produce enough of the hormones cortisol and aldosterone.
Another type of adrenal insufficiency is referred to as secondary adrenal insufficiency. This type of insufficiency occurs as a result of damage to the pituitary gland, which is a small gland located at the base of the brain. The pituitary gland is responsible for releasing a hormone that signals the adrenal glands to release cortisol and aldosterone. When the pituitary gland is damaged, it cannot signal the adrenal glands correctly, which results in an eventual shrinkage of the adrenal glands. Shrunken adrenal glands cannot function properly.
Symptoms
The Ohio State University Medical Center notes that symptoms may take months to appear. When symptoms do appear, they include fatigue, weakness, dizziness upon standing, nausea, vomiting, diarrhea, constipation, loss of appetite, stomachache, weight loss, increased sensitivity to cold, darkening of the skin and hair loss. Those with adrenal insufficiency may also experience a strong craving for salt or salty foods.
Hyponatremia and Fluid Restriction
One of the main functions of the kidneys is to retain and excrete the proper amounts of sodium and potassium, respectively. The stability of sodium and potassium in the body is important for proper blood pressure and fluid and salt balance. When aldosterone is not available in the body, the kidneys cannot maintain water and salt balance. This leads to a condition called hyponatremia, which is a low amount of sodium in the body. When sodium is too low, it causes blood pressure and blood volume to drop significantly. To return sodium levels back to normal, it is often necessary to restrict the intake of fluid so as not to further dilute the body cells. In addition to fluid restriction, it is also helpful to increase intake of salt.
Treatment
Treatment for adrenal insufficiency consists of supplementation with missing adrenal gland hormones. Supplementation usually requires intake of oral synthetic hormones for a lifetime. If blood pressure and blood volume have dropped to dangerously low levels, blood pressure medications may be needed until blood pressure returns to normal.
