Secondary adrenal insufficiency
definition
Secondary adrenal insufficiency is caused by a deficiency in the hormone ACTH (Adrenocorticotropic hormone). This is naturally produced in the pituitary gland and has a stimulating effect on the production of cortisol and the sex hormones, the so-called androgens.
The secretion of ACTH can be disturbed by pathological changes in the pituitary gland, also known as the adenohypophysis. As a result, there is no stimulating effect on the adrenal cortex and the body is insufficiently supplied with cortisol and androgens.
Possible causes
The cause of secondary adrenal insufficiency is usually a tumorous change in the pituitary gland. This is part of the human brain and produces certain hormones, such as ACTH (Adrenocorticotropic hormone).
The hormones of the adenohypophysis act as a messenger substance on other organs or tissues, as well as stimulating the adrenal cortex, and stimulate them to produce organ-specific hormones.
The release of ACTH normally leads to the secretion of cortisol and androgens in the adrenal cortex. If ACTH does not work, the adrenal cortex lacks its drive to produce the hormones mentioned - as a result, there is a lack of cortisol and androgens, which can manifest itself in a number of symptoms. The absorption of cortisol, as it occurs as a drug in many diseases, can also lead to a reduced secretion of ACTH. Some authors speak of tertiary adrenal insufficiency in this context, which is why the external supply of cortisol should be neglected here as the cause of secondary adrenal insufficiency.
Find out more about the topic here: Cortisone.
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The diagnosis
The diagnosis of secondary adrenal insufficiency results from the synopsis of the physical examination, the blood values and special tests that allow a differentiation of the adrenal insufficiency according to its cause.
Secondary adrenal insufficiency generally shows a decreased level of cortisol. The ACTH (Adrenocorticotropic hormone) The level in the blood is also reduced because the function of the pituitary gland is disturbed and hormone production fails as a result.
The cortisol deficiency alone does not allow any conclusions to be drawn about the cause of the adrenal insufficiency. The ACTH level in the blood and the result of the ACTH test are decisive, especially for differentiation into a primary or secondary disorder. In the ACTH test, those affected are given the hormone ACTH, which leads to a slight increase in cortisol in the event of a secondary disorder. In the case of primary insufficiency, however, there is usually no such effect.
Read more about the topic here: primary adrenal insufficiency.
The treatment
Secondary adrenal insufficiency is usually treated with medication. The missing cortisol is thus replaced.
The important thing is the dosage of cortisol, this can change depending on your physical condition or performance requirements. In the case of a febrile infection e.g. the body's cortisol requirement may increase - the externally supplied dose must then be adjusted accordingly. As a rule, this is explained in detail to those affected by the attending physician at the start of therapy.
In women with a loss of libido, i.e. the loss of sexual desire, DHEA can also be used (Dehydroepiandrosterone) are given. It is a so-called steroid hormone, which serves as the starting point for testosterone or estrogen production.
The course of the disease
With adequate therapy, secondary adrenal insufficiency can be expected to progress well. Of course, there may be deviations depending on the health of those affected. As a rule, however, the undesirable side effects of cortisol deficiency disappear with cortisol therapy.
In the treatment of secondary adrenal insufficiency, the correct dosage of the medicated cortisol is very important. In certain situations that are associated with a high level of stress or illness, the body's need for cortisol may be increased - this must then also be taken into account in the dosage.
If there is no therapy or insufficient cortisol substitution, Addison's crisis can occur. It is a life-threatening condition that requires medical treatment as soon as possible. The Addison crisis is a dreaded complication of adrenal insufficiency, the occurrence of which can usually be successfully countered with a well-adapted cortisol therapy.
More information on the topic Addison crisis you'll find here.
The duration
Secondary adrenal insufficiency can be effectively treated with the help of cortisol. The symptoms of renal cortical insufficiency then quickly regress in the course of therapy. The regular intake of cortisol and an adjusted dosage are necessary to avoid possible complications.
One of the possible consequences of a lack of cortisol is the Addison's crisis. This is life-threatening for those affected and can present with various symptoms such as diarrhea, nausea / vomiting, hypoglycaemia, drop in blood pressure, etc. If such a crisis occurs, immediate emergency medical treatment with cortisol and fluids is necessary. If left untreated, an Addison's crisis can lead to death.
How does cortisone work? Find out more about this here.
Difference from primary adrenal insufficiency
In primary adrenal insufficiency, the defect or disease lies in the organ itself. Here, it is not the ACTH deficiency in the hypofunction that is to blame, but in the majority of cases so-called autoimmune adrenalitis. These are autoimmune processes that lead to the destruction of the tissue - the body or the adrenal cortex destroys itself due to incorrectly controlled processes.
As with secondary adrenal insufficiency, there is also a lack of cortisol and androgen. Another hormone called aldosterone can also be affected. This has a decisive effect on the body's water and salt balance. The symptoms are sometimes almost the same. In contrast to secondary adrenal hypofunction, primary insufficiency can lead to a “darker coloration” of the skin.
Read more about the topic here: Symptoms of primary adrenal insufficiency.
Difference from tertiary adrenal insufficiency
Tertiary adrenal insufficiency is often described in the literature as a cortisol deficiency that arises after a dose reduction or the sudden discontinuation of drug-administered cortisol. That sounds a bit confusing at first, but it's easy to explain. The supply of cortisol tells the body that there is enough cortisol available. The otherwise driving force of the adrenal cortex, the pituitary gland, then releases less ACTH, so it is inhibited.
However, when the therapy suddenly ends or the dose is reduced, the body cannot react and the cortisol deficiency remains. Due to the pre-existing inhibition, the pituitary gland does not properly function. As a result, a so-called tertiary adrenal insufficiency is presented, which is similar in its symptoms to the secondary one.
Find out all about the topic here: Tertiary adrenal insufficiency.
