Acromegaly - Causes, Symptoms and Treatment .MF .
Acromegaly (Gigantism) - a disease in which increased production of growth hormone (growth hormone), thus there is a breach of the proportional growth of the skeleton and internal organs, in addition there is a metabolic disorder.
in childhood and adolescence with excessive growth activity developed gigantism and acromegaly develops after completion of growth.
This disease occurs very rarely and mostly in adults.
Growth Hormone has the following biological effects:
- causes bone growth in length - is the most important and the main function of growth hormone;
- enhances protein synthesis in bone, cartilage, muscle, liver and dr.organah;
- increases the production of glucagon (pancreas hormone that increases blood glucose);
- acting for 30-40 min, causing a decrease in blood glucose level, since it inhibits the enzymes cleaving operation glucose.
growth hormone regulates the hypothalamus, which secretes hormones stimulate (somatoliberin) and depressing (somatostatin) their products.
major role in the development of acromegaly is the increased production of growth hormone.The reason for increasing the production of growth hormone is an adenoma (benign tumor) of the pituitary, which has its own activity.Several less common cause can damage the hypothalamus and other parts of the brain (tumor, head injury with concussion, emotional and mental stress of the brain).
Symptoms of acromegaly
disease develops over the years.During acromegaly emit a series of stages.
- Preakromegaliya - is characterized by the early signs, it revealed quite rare, because the symptoms are not very pronounced.You must repeatedly investigate the level of growth hormone in the blood and make the computer brain tomography.
- Hypertrophic stage - characterized by severe symptoms.
- tumor stage - in the symptoms of the disease symptoms predominate influence on a number of organs and tissues located (increased intracranial pressure, eye and nerve disorders).
- cachectic stage - the stage of exhaustion - is the outcome of the disease.
clinical picture is manifested by the following symptoms:
- patients noted a headache, memory loss, impotence (in men), menstrual irregularities (in women), reduced vision.
- Patients with acromegaly acquire distinctive appearance: increased brow, ears, nose, tongue, cheek bones, lips, hands and feet (an increase mainly in width, which is why patients have to change the sizes of gloves, shoes, rings);lower jaw protrudes forward, increasing the gaps between the teeth;thickened skin, coarse folds on the face;thorax increased in volume.
- At the beginning of the disease there is an increase in muscle strength and health of patients, but the destruction of the muscle occurs later, with the result that there is muscle weakness and pain.
- There is increasing supply of cartilage that leads to akromegalicheskoy arthropathy (joint destruction).
- If the tumor is too severe, may occur compression of the optic nerve due to which there is blurred vision.
- With the progression of the disease may develop signs of a lesion of the internal organs (heart, lungs, kidneys): increased blood pressure, increased heart size due to an increase in the amount of muscle fibers, reducing blood flow.
- In 50-60% of patients have disturbances of stability (immunity) cells to glucose, while 1/5 of patients develop overt diabetes.
- If patients tumor "touches" the hypothalamus, the patients can occur drowsiness, thirst, polyuria, a sharp rise in temperature.
- Half of the patients have a diffuse or nodular goiter, which is associated with an increase in TSH.
diagnosis of acromegaly
Suspected acromegaly can already at detecting typical appearance change, especially the increase of the hands and feet.These changes can be seen even with a slight increase in growth hormone.However, diagnosis is established only on average 9 years after the appearance of the first symptoms.
to confirm the diagnosis and the search for the causes operate:
- General blood and urine analysis.
- Biochemical analysis of blood.
- ultrasound of the thyroid gland, ovary, uterus.
- X-rays of the skull and sella region (the formation of bone in the skull where the pituitary gland is) - there is an increase sella size or dual circuit.
- Computed tomography.
- Ophthalmologic examination (eye examination) - patients will be a decline in visual acuity, visual field restriction.
- A comparative study of photographs of the patient for the last 3-5 years.
Lung, liver, kidney, gastro-intestinal tract is to eliminate pituitary tumors that can produce growth hormone.
Laboratory tests confirm acromegaly
- Definition of secretion of growth hormone .The level of growth hormone in normally less than 1 ng / ml.Diagnostic importance of integrated level considered average & gt;2.5 ng / ml concentration
- study of blood IGF-1 .This test is the best diagnostic marker as the only reason for the increase of IGF-1 in the blood is an increase in daily production of growth hormone.
- Oral glucose tolerance test (OGTT) with taking 75 g of glucose .The absence of reduction of growth hormone levels below 1 ng / ml is a diagnostic criterion for acromegaly.
treatment of acromegaly
operation - the main method of treatment of acromegaly.
If there are signs of compression of adjacent structures to the tumor, shows emergency surgery.In these cases, to recommend to the preoperative preparation of somatostatin analogues inappropriate.It is best to use drug therapy after surgery.The probability of success higher.
But at the same time, if the patient's condition is unstable at high risk of complications of general anesthesia (due to the destruction of the respiratory tract) or there are severe systemic manifestations of acromegaly (cardiomyopathy, severe hypertension, decompensated diabetes), medication is preferable.
Somatostatin analogues - inhibitors of growth hormone secretion;
receptor antagonists of growth hormone - a new group of drugs that directly block the action of growth hormone and decreases the synthesis of IGF-1 - pegvisomat (Somavert)
stimulants dopamine receptors - cabergoline (Dostinex) and bromocriptine (Parlodel, abergin) - much less effective than the first two groups,but there is evidence that the ineffectiveness of monotherapy with somatostatin analogues helps add some patients dopamine receptor stimulants.
outcome is exhaustion (cachexia).In the absence of appropriate treatment, an unfavorable course and early start (at a young age), life expectancy of patients is 3-4 years.With slow development and congenial person can live 10 to 30 years.
With timely treatment, the prognosis for a favorable life may recover.Employability of patients is limited.