Syndrome and disease Cushing's ( hypercortisolism ) - Causes, Symptoms and Treatment .MF .
Syndrome Cushing or hypercortisolism - a condition caused by prolonged exposure to high levels of glucocorticoids body hormones, the most important of which is cortisol.
Cortisol is produced in the adrenal cortex.The main stimulator of cortisol is adrenokortikotropnyygormon (ACTH).ACTH is produced in the pituitary gland - endocrine gland located at the base of the brain.ACTH stimulates Development corticotropin-releasing hormone, which is produced in the hypothalamus - a brain region controlling the body's endocrine system.
Cortisol performs vital tasks in the body.It helps maintain blood pressure in the cardiovascular system, reducing the inflammatory response of the immune system, balances the effect of insulin, increasing blood glucose levels, regulates the metabolism of proteins, carbohydrates and fats.One of the most important tasks of cortisol to help the body respond to stress.For this reason women in the last 3 months of pregnancy and professional athletes tend to have high levels of cortisol.
Normally, when the amount of cortisol in the blood is adequate, the pituitary gland produces less ACTH.A reduction in ACTH cortisol content increases to more strongly stimulate the production of adrenal glucocorticoids.This ensures that the amount of cortisol produced by the adrenal glands, enough to meet the body's daily needs.
excess cortisol in the following cases:
1. Long-term use of glucocorticoids, such as prednisone, dexamethasone, for the treatment of bronchial asthma, rheumatoid arthritis, systemic lupus erythematosus, and other inflammatory diseases, or for immunosuppression afterorgan transplant - exogenous (caused by external influences) giperkortizizm .
2. adenoma (benign tumor) of the pituitary - the main cause of Cushing's syndrome.Hypercortisolism caused by pituitary adenoma, local doctors call disease Cushing's , all other cases of Cushing - actually syndrome Cushing.pituitary adenoma releases increased amounts of ACTH and ACTH, in turn, stimulates the excessive production of cortisol.This form of the syndrome affects women five times more frequently than men.
3. syndrome of ectopic ACTH production - a condition in which benign or malignant (cancerous) tumor outside the pituitary gland to produce ACTH.Lung tumors cause more than 50% of these cases.The most common forms of ACTH-producing tumors of the lung are ovsyanokletochny or small cell lung cancer tumor ikartsinoidnye.Men are affected three times more often than women.Other, less common types of tumors that can produce ACTH are thymoma (a tumor of the thymus glands), pancreas, and thyroid cancer.
4. tumors of the adrenal glands.Cushing's syndrome is sometimes caused by a pathology, often tumor, adrenal glands, which secrete excessive amounts of cortisol.In most cases of adrenal benign tumor (adenoma).Adrenocortical carcinoma, or adrenal cancer is the least common cause of Cushing's syndrome.Adrenocortical carcinomas usually cause very high hormone levels increase and the rapid development of symptoms.A very rare cause of Cushing's syndrome is adrenal hyperplasia of the adrenal cortex, ie,an abnormal increase in the number of cortical cells.In all forms of the syndrome of adrenal Cushing's blood ACTH level is lowered.
5. familial form of Cushing's syndrome .Most cases of Cushing's syndrome are not inherited.However, very rarely the cause of this syndrome is a hereditary disease - a syndrome of multiple endocrine neoplasia, ietendency to develop tumors of one or several endocrine glands.In this disease, along with adrenal tumor may be present tumors of the parathyroid glands, the pancreas and the pituitary gland that produce relevant hormones.
Syndrome Symptoms Cushing's
Most patients with hypercortisolism are obese.Weight gain - one of the earliest signs of the disease.fat deposition is mainly torso, face, neck.And the limbs, on the contrary, become thinner.
in childhood and adolescence, as a rule, along with obesity is marked slowing in growth rate.
very characteristic of Cushing are skin changes.The skin is thin, marked bruising, bruising, which are very long.May appear wide purplish pink, purple stretch marks on the abdomen, thighs, buttocks, arms and chest.
striae with Cushing's syndrome
Sometimes patients complain of pain in the back, ribs, arms and legs in motion.This is because the Cushing's syndrome often leads to osteoporosis.Osteoporosis is a decrease in bone density, a violation of their structure, increased brittleness and decreased strength, which may lead to fractures even at the slightest trauma.
Syndrome Cushing's is accompanied by fatigue, muscle weakness, irritability, anxiety, rarely changes the psyche.
One of the early symptoms of the syndrome is an increase in blood pressure. Since glucocorticoids suppress the effect of insulin, often with hypercorticoidism rises in blood sugar and symptoms of diabetes (thirst, frequent, copious it.d.).
Women usually have excess hair growth on the face, neck, chest, skin, stomach and thighs.Menstruation may become irregular or stop.Men celebrate decreased libido.
If you experience any of the symptoms of Cushing's, and especially their combination, it is necessary both to seek medical help as soon as possible.
Diagnosing Cushing's syndrome
task of the first stage of diagnosis - to determine whether there is an increase in cortisol levels.For this purpose, special test - determination of Cortisol in daily urine.
The patient urine collected over a 24 hour period, determined by the level of cortisol.Levels higher than 50-100 mg per day for adults, Cushing's syndrome is confirmed.The upper limit of the normal range varies in different laboratories, depending on the measurement technique.After identifying
increase cortisol levels to be detected current location of the process that leads to excessive production of cortisol.
Test with dexamethasone helps to distinguish patients with excess ACTH production due to pituitary adenomas from those with ectopic ACTH-producing tumor.The patient takes the dexamethasone (a synthetic glucocorticoid) orally every 6 hours for 4 days.During the first two days are given lower doses of dexamethasone in the last 2 days - higher.Produced daily urine collection before the administration of dexamethasone and forth every day of the test.When pituitary adenoma the level of cortisol in the urine is reduced, as is the pituitary gland cortisol levels did not change when the ectopic tumor.To do this test you need to stop taking drugs such as phenytoin and phenobarbital in one week.
depression, alcohol abuse, high estrogen levels, acute illness and stress can lead to an incorrect result.Therefore, preparation for the test to be careful.
Stimulation test with corticotropin-releasing hormone .This test helps to distinguish between patients with pituitary adenoma patients from syndrome of ectopic production of ACTH and cortisol-secreting adrenal tumors.The patient is injected with a corticotropin-releasing hormone, which causes the pituitary gland to produce ACTH.In adenoma pituitary ACTH and cortisol levels in the blood increase.This answer is very rarely seen in patients with ectopic ACTH production syndrome and practically never in patients with cortisol-secreting adrenal tumors.
next diagnostic step is direct visualization of the endocrine glands .The most commonly used ultrasound adrenal computed tomography or magnetic resonance imaging of the pituitary, adrenal glands.To establish the ectopic ACTH production hearth used ultrasound, CT or MRI of the relevant body (usually the chest, thyroid, pancreas).
syndrome Treatment of Cushing's
Treatment depends on the specific cause of excess cortisol and may include surgery, radiation or drug therapy techniques.
If the cause of the syndrome is a long-term use of glucocorticoid hormones to treat another disease, you need a gradual reduction in dose to the minimum dose sufficient to control the disease.
For the treatment of pituitary adenoma, the most widely used surgical removal of the tumor, known as transsphenoidal prostatectomy .Using a special microscope and very fine endoscopic instruments, the surgeon approaches the pituitary gland through a nostril or an opening made under the upper lip, and remove the adenoma.The success of surgery depends on the surgeon's skill, is more than 80 percent, when a surgeon with extensive experience.After surgery, pituitary ACTH production dramatically decreases and patients receive substitution therapy with glucocorticoids (such as hydrocortisone or prednisolone) are usually required during the year, then the products recovered ACTH and glucocorticoids.
For patients with contraindications to surgery may conduct radiotherapy .This method takes about 6 weeks, the efficiency is 40-50%.The disadvantage of this method is the latency of improvement, the effect may occur in a few months or even years after exposure.However, a combination of radiation and drug therapy mitotanom (Lizodren) can help speed recovery.Mitotane suppresses cortisol production.Treatment only mitotanom can be successful in the 30 to 40% of cases.
There are other drugs used in hypercorticoidism alone or in combination: aminoglutethimide, metyrapone and ketoconazole.Each of them has its own side effects that doctors consider when assigning therapy for each patient individually.
The syndrome of ectopic ACTH production is most preferred surgical removal of ACTH-secreting tumor.In cases where the tumor is found in the inoperable stage used adrenalectomy - removal of the adrenal glands.This operation is somewhat alleviates the symptoms in these patients.Sometimes used and drug treatment (metyrapone, aminoglutethimide, mitotane, ketoconazole).
When adrenal tumors surgical method is the basis for the treatment of both benign and malignant adrenal tumors.
endocrinologist Faizulin NM