Cushing's syndrome, also known as hypercorticosteroidism, occurs when a person's tissues are exposed to too much of hormone cortisol.
When adrenal glands release right amount of cortisol, it helps regulate blood pressure, energy production, ability to fight disease, and how body maintains itself and responds to stress. But too much cortisol can change normal function of these processes, leading to symptoms of Cushing's syndrome.cause
The body produces too much cortisol. When pituitary and adrenal glands are not working properly, they produce too much cortisol. Reasons for this:
Adrenal growths, which may or may not be cancerous, cause adrenal glands to secrete extra cortisol.
A non-cancerous tumor of pituitary gland that produces large amounts of adrenocorticotropic hormone (ACTH). This, in turn, encourages adrenal glands to produce too much cortisol. This form of Cushing's syndrome is called Cushing's disease. Cancer of Adrenal Cortex Certain cancers elsewhere in body can produce ACTH, causing adrenal glands to produce extra cortisol. ACTH-secreting pituitary adenomas and nonpituitary tumors produce ectopic ACTH.Clinical suspicion
High blood pressure (especially in young people), diabetes and overweight (central type), especially if:
Cushing's syndrome is rare. Between 2 and 5 new cases per million people are diagnosed each year, 10% of which occur in children and adolescents.
Most children and adolescents with Cushing's syndrome show the following symptoms:
Adults with this condition may also experience symptoms of dramatic weight gain, excessive hair growth, high blood pressure, and skin problems. In addition, they may indicate:
The doctor reviews patient's medical records and performs a physical examination. If these findings are indicative of Cushing's syndrome, additional tests will need to be performed. The final diagnoses include:
Confirm diagnosis using one of following methods.
The high-dose dexamethasone suppression test suppresses Cushing's disease but not other causes after confirmation by one of above tests. Plasma ACTH levels determine whether ACTH plays a role in pathogenesis. CT or MRI of pituitary or adrenal glands to look for adenomas. A chest x-ray is necessary to rule out bronchial carcinoma or carcinoid.
Note: Cushing's disease refers to hypercorticosteroids secondary to ACTH-secreting pituitary adenomas.treatment
Regardless of its underlying cause, cortisol hypersecretion should be controlled prior to surgery or radiation therapy to reduce morbidity and mortality in patients who are not ready for surgery.
If an adrenal adenoma is found, it can be surgically removed. Steroid replacement therapy is required in most patients in postoperative period, at least in medium term, because long-term suppression of pituitary ACTH and normal adrenal tissue cannot be restored immediately. Obviously, if both adrenal glands are removed, replacement with hydrocortisone or prednisolone is necessary.
In those patients who are unsuitable or unwilling to undergo surgery, several drugs have been found to inhibit cortisol synthesis (eg, ketoconazole, meladone) but have limited efficacy. In iatrogenic Cushing's syndrome, a dose adjustment may be sufficient or a change to a different type of immunosuppressant may be required.
Meravon is drug of choice. The average level of plasma cortisol during day should decrease to 11-15 mcg / l. Alternatively, ketoconazole or aminomethylacetamide can be used.
The definitive treatment is resection of source of hypersecretion, be it pituitary gland, adrenal gland, or ectopia.