Acromegaly - Causes, symptoms and treatment. MF.

Acromegaly( gigantism) - a disease in which the production of growth hormone( somatotropin) increases, with a violation of proportional growth of the skeleton and internal organs, in addition, there is a metabolic disorder.

In childhood and adolescence, with excessive growth activity, gigantism develops, and after the completion of growth, acromegaly develops.

This disease develops very rarely and mostly in adults.

Somatotropin has the following biological effects:

• causes bone growth in length - this is the most important and basic function of growth hormone;
• enhances protein formation in bones, cartilage, liver and other organ organs;
• increases the production of glucagon( a pancreatic hormone that increases blood glucose);
• acting for 30-40 minutes, causes a decrease in blood glucose, as it inhibits the work of glucose-cleavage enzymes.

The production of growth hormone is regulated by the hypothalamus, in which hormones stimulating( somatoliberin) and oppressive( somatostatin) are produced.

Causes of acromegaly

The main role in the development of acromegaly is the increase in the production of growth hormone. The reason for increasing production of growth hormone is the adenoma( benign tumor) of the pituitary gland, which has its own activity. More rarely, the cause may be damage to the hypothalamus or other parts of the brain( tumors, trauma to the skull with concussion, emotional and mental stress of the brain).

Symptoms of acromegaly

The disease has been developing for years. During acromegaly, a number of stages are distinguished.

1. Preacromegaly is characterized by the earliest signs, it is quite rare, because the symptoms are not very pronounced. It is necessary to repeatedly study the level of somatotropin in the blood and do a computer tomography of the brain.
2. Hypertrophic stage - characterized by severe symptoms.
3. Tumor stage - symptoms of the disease are dominated by signs of influence on nearby organs and tissues( increased intracranial pressure, eye and nerve disorders).
4. The cachectic stage - the stage of exhaustion - is the outcome of the disease.

The clinical picture is manifested by the following symptoms:

1. Patients with headache, memory impairment, sexual weakness( in men), menstrual disorders( in women), decreased vision.
2. Patients with acromegaly acquire a characteristic appearance: an increase in the superciliary arches, ear shells, nose, tongue, cheek bones, lips, hands and feet( enlargement is mainly in width, due to which patients are forced to change the sizes of gloves, shoes, rings);the lower jaw protrudes forward, the spaces between the teeth increase;the skin is thickened, with coarse creases on the face;the thorax is enlarged in volume.
3. At the beginning of the disease there is an increase in muscle strength and performance of patients, but later there is a destruction of muscles, resulting in muscle weakness and soreness.
4. There is an increase in the supply of cartilaginous tissue, which leads to the appearance of acromegaly arthropathy( joint destruction).
5. If the tumor is too pronounced, compression of the optic nerves may occur due to which vision deterioration occurs.
6. When the disease progresses, signs of damage to the internal organs( heart, lungs, kidneys) can develop: increased blood pressure, increased heart size due to increased muscle fibers in the volume, decreased blood circulation.
7. In 50-60% of patients, there are violations of resistance( insensitivity) of cells to glucose, and in 1/5 of patients develops obvious diabetes mellitus.
8. If in patients the tumor "touches" the hypothalamus, then patients may experience drowsiness, thirst, polyuria, sudden temperature rises.
9. Half of patients have a diffuse or nodular goiter, which is associated with an increase in thyrotropin.

Diagnosis of acromegaly

Acromegaly can be suspected even with the detection of characteristic changes in appearance, especially the increase in brushes and feet. These changes can be seen even with a slight increase in the STG.Nevertheless, the diagnosis is established on average only 9 years after the onset of the first symptom.

To confirm the diagnosis and to find the cause, perform:

1. General analysis of blood and urine.
2. Biochemical blood test.
3. ultrasound of the thyroid gland, ovaries, uterus.
4. X-ray of the skull and the area of ​​the Turkish saddle( bone formation in the skull, where the pituitary gland is located) - there is an increase in the size of the Turkish saddle or two-contour.
5. Computed tomography.
6. Ophthalmological examination( examination of the eyes) - patients will be noted reduced visual acuity, limiting visual fields.
7. Comparative study of photos of the patient for the last 3-5 years.

Study of the lungs, liver, kidneys, gastrointestinal tract to exclude tumors outside the pituitary that can produce somatotropin.

Laboratory tests confirming acromegaly

• Definition of secretion of STG .The level of STH is normally less than 1 ng / ml. Diagnostically significant is the average integrated level & gt;2.5 ng / ml
• Study of blood concentrations of IGF-1 .This test is the best diagnostic marker, since the only reason for increasing IGF-1 in the blood is an increase in the daily production of STH.
• Oral Glucose Tolerance Test( OGTT) with the intake of 75 g of glucose .The absence of a decrease in the level of the STH below 1 ng / ml is the diagnostic criterion for acromegaly.

Treatment of acromegaly

Surgical method

Operation is the main method of treating acromegaly.
If there are signs of squeezing of the adjacent tumor structures, an emergency operation is indicated. In these cases, it is not advisable to recommend preoperative preparation with analogues of somatostatin. It is better to apply medication after surgery. The probability of success is higher.
However, if the patient's condition is unstable, the risk of complications of general anesthesia( due to the defeat of the respiratory tract) or severe systemic manifestations of acromegaly( cardiomyopathy expressed by AH, decompensated diabetes mellitus) is high, medication is preferable.

Medication

Somatostatin analogues are inhibitors of STH secretion;
Antagonists of STH receptors - a new group of drugs that directly blocks the effect of STH and reduces the synthesis of IGF-1 - Pegvisomate( Somavert)
Dopamine receptor stimulators - cabergoline( Dostinex) and bromocriptine( Parlodel, Aberghin) are much less effective than the first two groups,but there is evidence that when monotherapy with somatostatin analogues is ineffective, some patients are helped by the addition of stimulants of dopamine receptors.

Forecast of acromegaly

The outcome of the disease is depletion( cachexia).In the absence of appropriate treatment, with unfavorable course and early onset( at a young age), the life expectancy of patients is 3-4 years. With a slow development and a favorable current, a person can live from 10 to 30 years.

With timely treatment, the prognosis for life is favorable, it is possible to recover. The incapacity of patients is limited.