What are the adrenal glands?
The adrenal glands are small structures located on top of each kidney. They have different shapes: the right one is pyramidal and the left one is crescent-shaped. They are responsible for producing hormones essential for life and their function is to regulate stress responses through the synthesis of corticosteroids (especially cortisol) and catecholamines (adrenaline). Cortisol helps to respond to stress, among other functions.
The adrenal glands are also not located in exactly the same place. The left adrenal gland is not quite superior but medial. These glands are supplied by branches of the inferior phrenic artery, the middle adrenal artery (a branch of the aorta of the abdomen), by the superior polar artery (which comes from a branch of the renal artery) and by the exorenal arch of the kidney.
Function of the adrenal glands
The adrenal glands are small but have a very important function in the body, producing multiple hormones involved in development, growth and affecting our ability to handle stress, as well as regulating kidney function.
Thus, the adrenal glands have two functions, a nervous and an endocrine function:
- Endocrine function. They secrete hormones involved in the regulation of electrolyte/hydrate balance. Also other hormones that maintain the correct levels of glucose, proteins and fats, with catabolic, anti-inflammatory and thermogenic functions. They also produce anabolic and masculinizing hormones.
- Nervous function. The glands allow a correct response to stress.
Pathologies that can affect the adrenal glands
To know the pathologies that can affect the adrenal glands, it is important to know their structure. The adrenal gland is divided into 2 parts:
- Medulla, which produces adrenaline and noradrenaline, substances that are responsible for activating the heart rate and respiration.
- Cortex, which generates glucocorticoids (hydrocortisone) and is in charge of mobilizing the energy we need.
The brain is the one that processes all the information and activates the different systems of the body, depending on the situations we face, so the influence on the adrenal glands will come from there. The diseases that the adrenal glands may suffer will depend on the affected area and there may be both excess and deficiency of production, as well as mixed pictures.
On the other hand, tumors can also cause disorders in the adrenal glands and hemorrhages and infections can cause adrenal problems.
Thus, if there is an excessive production of hormones the alteration is in the gland itself and the symptoms that the patient has will depend on which hormone is being produced in excess:
- Increased testosterone-like hormones. This can occur in both men and women, and will produce a virilization or excessive development of masculine characteristics. Sometimes it occurs moderately, and only as an increase in hair (hirsutism).
- Cushing’s syndrome. It is a hyperproduction of corticosteroids, which can have several causes. If primary it may be due to adrenal carcinoma, adrenal adenoma or adrenal hyperplasia. If secondary, it may be due to an ACTH-secreting pituitary microadenoma (Cushing’s). A tertiary one, due to hypothalamic hypersecretion of CRH, which can be tumorous or not. In parallel, there may be an ectopic secretion of ACTH, something frequent in patients with bronchial carcinomas, or ectopic secretion of CRH (in carcenoid tumors). Or a iatrogenic one, by chronic use of ACTH or cortisol.
When there is an excess of corticosteroids, the distribution of body fat is altered, so that patients tend to have a characteristic appearance: a very rounded full moon face, a lot of fat in the torso, loss of muscle mass with weakness, thin skin, red striae in the abdominal area… They also tend to have high blood pressure, osteoporosis and lower resistance to infections. There is also a higher risk of kidney stones, diabetes and depression.
In addition, other pathologies can be:
- Hyperaldosteronism or hyperproduction of Aldosterone. It is the hormone in charge of regulating ions at renal level such as sodium, chlorine, bicarbonate and potassium. Its increase modifies blood concentrations, with an increase in blood pressure, among others. It is usually caused by tumors, but not always cancerous.
- Excessive secretion of catecholamines (adenaline, dopamine, noradrenaline), usually caused by a tumor (pheochromocytoma) affecting the adrenal glands. The increase of these catecholamines produces an increase in blood pressure and sometimes patients suffer panic attacks, with accelerated pulse, excessive sweating, palpitations, increased respiratory rate…
On the other hand, there are the pathologies of the adrenal glands produced by a low production of hormones:
- Addison’s disease, which is usually caused by diseases of the adrenal glands. Its main causes are Autoimmune Adrenalitis or Tuberculosis but other causes can be: disseminated intravascular coagulation, fungal diseases, surgeries, Amyloidosis, drugs that inhibit enzymes that synthesize cortisol, AIDS or other congenital diseases.
When there is a deficit of hormones in the body, different disorders can occur:
- Problems maintaining adequate levels of potassium and sodium in the blood.
- Since the kidney cannot store urine, the patient needs to go to the bathroom frequently. In addition, dehydration and shock may occur.
- Increased insulin sensitivity, with decreased blood sugar levels.
- Accumulation of hormones produced by the brain to stimulate the adrenal gland, which affects the production of melanin (skin pigment), so that some patients may suffer from darkening of the skin and the inner area of the mouth.
Treatments for adrenal gland pathologies
Specialists will employ various surgical and pharmacological treatments for diseases of the adrenal glands, which may include:
- Medications to curb excessive hormone production.
- Hormone replacement.
- Surgery to remove tumors of the adrenal glands or, if necessary, surgery to remove one or both glands.
In Cushing’s syndrome, treatment will depend on the cause. If there is an excess of cortisol from a medication, the specialist may change the dose or try to change the medication. If the body produces too much cortisol, medication or radiotherapy may be administered.
In pheochromocytoma the usual treatment is resection of the tumor, which improves the patient’s blood pressure.
In Addison’s disease, the cortisol or aldosterone that the body lacks is replaced. Patients will receive daily medications to replace the hormones and may also be advised to eat more salt.
In hyperaldosteronism, treatment will depend on what is causing the disorder. Thus, the effect of aldosterone may be blocked or the adrenal gland may need to be resected in cases of tumors.
Specialist who treat adrenal gland pathologies
Specialists who treat adrenal gland pathologies may be experts in General Surgery and/or Endocrinology.