Addison’s disease is a disorder that occurs when the adrenal glands (located above the kidneys) produce insufficient amounts of hormones such as cortisol and aldosterone, which are important hormones for every organ in the body.
The adrenal glands are separated into two sections: The interior (medulla) produces adrenaline-like hormones while the outer layer (cortex) produces corticosteroid hormones including glucocorticoids, mineralocorticoids and androgens (male sex hormones).
- Glucocorticoids: cortisol containing hormones help the immune system’s inflammatory response and help the body respond to stress.
- Mineralocorticoids: these hormones contain aldosterone and maintain the amounts of sodium and potassium in the body to control the blood pressure.
- Androgens: male sex hormones produced in small amounts by the adrenal glands. They cause sexual development in men and affect muscle mass and libido in both genders.
In addition, cortisol’s functions are vital for the body’s health and help to regulate blood pressure, blood sugar levels, the immune system and the body’s response to stress. On the other hand, aldosterone is a hormone that regulates salts in the blood and also helps to control the blood pressure.
Addison’s disease is also referred to as adrenal insufficiency and it can be a life-threatening disease that occurs in both sexes and all age groups.
The treatment generally involves taking hormones to make up for the insufficient levels in order to achieve beneficial effects as naturally produced hormones.
Symptoms of Addison’s disease usually develop slowly and may be difficult to identify because some of the early symptoms are similar to symptoms of other conditions.
Primary symptoms of Addison’s disease involve:
- Muscle weakness
- Decreased appetite or unexplained weight loss
- Low blood sugar (hypoglycemia)
- Muscle or joint pain
- Low blood pressure
- Darkening of skin (hyperpigmentation)
- Nausea, diarrhea or vomiting
- Salt craving
- Increased thirst
- Sexual dysfunction in women
More progressive symptoms may occur due to increased stress or other factors and cause an addisonian crisis also known as acute adrenal failure.
In acute adrenal failure the symptoms may appear suddenly in the form of:
- Low blood pressure
- Nausea and loss of consciousness
- Abdominal, joint and back pain
- Sever vomiting and diarrhea resulting in dehydration
- High potassium (hyperkalemia)
- Chronic exhaustion
Very rare symptoms of Addison’s disease include sweating and psychosis.
In women the condition may cause sexual dysfunction and irregular periods while children with this disease may experience puberty later than usual.
Addison’s disease develops as a result of damage in the adrenal cortex (outer layer of the adrenal glands). Thus the level of hormone production becomes reduced. The causes of Addison’s disease can be categorized as primary and secondary adrenal insufficiency.
Primary adrenal insufficiency
Damage to the adrenal glands is identified as primary adrenal insufficiency. Insufficient production of adrenocortical hormones is usually a result of an autoimmune disease (the body attacking itself). In this case the autoimmune disease causes the immune system to attack the adrenal cortex because it perceives it as something foreign.
Other causes of adrenal gland failure include:
- Infections of the adrenal glands
- Cancer that has spread to the adrenal glands
- Adrenal gland bleeding
Secondary adrenal insufficiency
A diseased pituitary gland can also cause adrenal insufficiency. The pituitary gland produces the hormone adrenocorticotropic, which stimulates the adrenal cortex to produce hormones. Inadequate or insufficient production of the adrenocorticotropic hormone (ACTH) leads to insufficient hormone production by the adrenal glands.
Nonetheless, a more common cause of secondary adrenal insufficiency is a sudden stop in taking corticosteroids for underlying chronic conditions such as asthma or arthritis.
Untreated Addison’s disease can lead to an addisonian crisis which may be triggered by physical stress, infection or illness.