Suprarrenal insufficiency

Adrenal insufficiency is a deficit in the manufacture of steroid hormones (glucocorticoids and mineralocorticoids) by the adrenal glands.

How is it produced?

Glucocorticoids and mineralocorticoids are manufactured by the adrenal glands. This production of glucocorticoids is stimulated by another hormone called ACTH (adrenocorticotropic hormone) that is synthesized in the pituitary gland. In turn, ACTH is stimulated by another hormone made by the hypothalamus. Mineralcorticoids are regulated by substances such as renin and angiotensin.

Cases of adrenal insufficiency can be divided into two large groups: 1) those related to the inability of the adrenal glands themselves to manufacture these hormones in sufficient quantity (Addison's disease), and 2) those secondary to insufficient ACTH manufacture.

The most common cause of Addison's disease is what is called autoimmune adrenalitis, that is, inflammation and destruction of the adrenal glands by antibodies against the adrenal glands that can sometimes appear accompanied by the involvement of other glands. Other causes of Addison's disease are infections like tuberculosis and others. There are also hemorrhagic causes such as in the case of Waterhouse-Friderichsen syndrome or in cases associated with the use of anticoagulants. Tumor metastases from other sites, surgical removal of the adrenal glands, or treatment with adrenal inhibitors such as mitotane, ketoconazole, aminoglutethimide, or methopyrone may be associated with primary adrenal insufficiency. Sometimes there may not be a destruction on the gland but there is resistance to the action of ACTH through antibodies that block the action of ACTH so that the gland, although healthy, will not synthesize or secrete corticosteroids.

The causes of secondary adrenal insufficiency are due to affectations of the pituitary or hypothalamus that present with a lack of ACTH secretion.

External steroid treatment inhibits ACTH secretion and corticosteroid secretion by the adrenal glands. The same occurs when there is a tumor from any other location that produces corticosteroids. In these cases, when corticosteroids are eliminated from the blood either because we no longer use the drug or because we remove the tumor that produced them, an adrenal crisis will be triggered since the glands were previously inhibited.

In primary adrenal insufficiency, both glucocorticoids and mineralocorticoids are affected, however in the case of secondary adrenal insufficiency, only glucocoticosteroids are affected.

Symptoms

The symptoms will be derived from glucocorticoid deficiency. Generally, the clinical manifestations usually appear gradually and include weakness, fatigue, weight loss, nausea, vomiting, diffuse abdominal pain of a generally mild nature.

When the involvement is primary and the mineralocorticoids are also affected. In this situation, symptoms such as a craving for salt, and episodes of hypotensive dizziness are usually added, especially when we get up after having been lying down for a while. These symptoms are due to sodium loss due to mineralocorticoid deficiency.

In primary adrenal insufficiency, there is usually an increase in ACTH as the well-functioning pituitary gland does not detect corticosteroids in the blood and increases ACTH production to stimulate corticosteroid production. This produces an increase in skin pigmentation in areas that are not exposed to sunlight.

Because steroids are not manufactured in the adrenal gland, women may lack pubic and armpit hair since they are the main source of androgens, unlike men where the main androgen is testosterone manufactured by the testicles.

Other symptoms such as calcifications in cartilage and joints may also appear.

Sometimes there may be an adrenal crisis, generally due to a sudden decrease in corticosteroids in the blood. It usually occurs when a patient is on drug treatment with steroids that inhibit the generation of corticosteroids by the adrenal gland and suddenly stops receiving that treatment, other times it can occur due to hemorrhagic destruction of the adrenal glands or situations of excessive effort on the part of the body as in serious infections, burns, etc. In this case the symptoms include very high fever, nausea, vomiting, severe hypotension and if not resolved shock.

Diagnosis

The diagnosis is made by measuring cortisol levels in the blood, which will be lowered. This is done after giving synthetic ACTH. Furthermore, in the case of primary insufficiency or Addison's disease, ACTH levels will be increased, but not in the case of secondary insufficiency where ACTH will be decreased.

Imaging tests such as abdominal ultrasound and, preferably, CT or MRI of the abdomen can reveal morphological alterations of the gland.

Treatment

In general, treatment will be based on the replacement of corticosteroid hormones. In the case of primary insufficiency or Addison's disease, both glucocorticoids and mineralocorticoids will be administered, while if it is secondary, only glucocorticoids will be administered. In general, the administration of glucocorticoids includes pharmacological preparations based on cortisone, hydrocortisone, prednisone or dexamethasone. Substitutes for mineralocorticoids include fludrocortisone.

It is necessary to know that in stressful situations such as surgeries, trauma, among others, they will require an increase in dose, so the patient must be trained to handle their medication.

In cases of secondary adrenal insufficiency, in general, treatment with glucocorticoids is usually sufficient. The adrenal crisis is a medical emergency and requires high doses of intravenous cortisol and abundant hydration through serum, in hospital.

Precautionary measures

Prevention happens because in individuals under prolonged treatment with corticosteroids, they are not withdrawn abruptly, and the dose is increased under stress, for example, infections, surgeries, or trauma. In the other cases, there is no possibility of disease prevention.