Acromegalia

Description:

Acromegalia - the serious, chronic neuroendocrinal illness arising owing to excess products of a growth hormone adenoma of a hypophysis (somatotropinomy).

Acromegalia symptoms:

The acromegalia is, as a rule, characterized by the gradual beginning with slow increase of symptomatology and change of appearance. The diagnosis of an acromegalia on average is established approximately in 7 years after the real beginning of a disease. The main symptoms are:

    * Changes of appearance are very characteristic and in most cases they allow to suspect an acromegalia. The coarsening of features connected with increase in superciliary arches, malars, a mandible is characteristic. The hypertrophy of soft tissues of the person is noted: nose, lips, ears. Increase in a mandible leads to change of a bite due to discrepancy of interdental spaces. Language is increased (macroglossia), in it prints of teeth are often visible. Change of appearance develops rather slowly so the patient does not notice it. Besides, there is an increase in the sizes of brushes and feet (patients often point to increase in the size of footwear, sometimes considerable). At giantism, unlike an acromegalia, there is an increase in linear growth.

The expressed hypertrophy of cartilaginous tissue of joints causes arthralgias. Increase in quantity and increase in functional activity of sweat glands lead to considerable perspiration (at survey it is possible to see sometimes the sweat streamlets which are flowing down on the patient's body). Activation and a hypertrophy of sebaceous glands, a thickening of skin lead to its characteristic look (dense, reinforced, with the deep folds which were more expressed on a pilar part of the head).

    * A splanchnomegaly with the subsequent development of organ insufficiency. Influence of a growth hormone on muscles and internals at the initial stages of a disease is hardly noticeable, and at times, especially at athletes and persons of physical work is perceived positively as working capacity and physical activity increase, but in process of progressing of a disease muscle fibers degenerate, causing the increasing weakness, the progressing decrease in working capacity. Noncompensated long hyperproduction of a growth hormone leads to development of a concentric hypertrophy of a myocardium which is replaced by a hypertrophic myocardial dystrophy, and in the started cases it passes in dilatatsionny that leads to the progressing heart failure, being a cause of death of patients. At 30% of patients with an acromegalia arterial hypertension comes to light.
    * The headaches connected with destruction of the Turkish saddle, its diaphragm and intracranial hypertensia.
    * The apnoea syndrome in a dream develops at 90% of patients with an acromegalia. It is connected with growth of soft tissues of upper respiratory tracts and defeat of respiratory centers.
    * Pituitary insufficiency is connected with destruction and a prelum of a hypophysis a tumor. Reproductive frustration (disturbances of a menstrual cycle, erectile dysfunction), in addition to disturbance of products of gonadotrophins, are often connected with a giperprolaktinemiya which can be in turn connected with the accompanying prolactin hyperproduction by a tumor, or with a hypophysis leg prelum.
    * Hiazmalny syndrome.
    * A symptomatic diabetes mellitus (to 50% of patients).
    * Development of benign and malignant tumors of various localization owing to a chronic giperpoduktion of growth factors (IRF-1, etc.). At an acromegalia quite often reveal a nodal or diffusion craw, an adenomatous adrenal struma, a fibrous and cystous mastopathy, a hysteromyoma, a polycystosis of ovaries, intestines polyposes. Polyps of intestines meet in 20-50% of cases, intestinal adenocarcinomas - in 7% of all cases of an acromegalia.

Acromegalia reasons:

At a hypophysis adenoma acromegalia, cosecreting a growth hormone, come to light in 99% of cases. Immunohistochemical, in addition to pure somatotropic adenomas (about 45%), allocate the mixed prolaktosomatropinoma (about 30%). Other 25% of adenomas, besides, produce other adenogipofizarny hormones: TTG, and - subunit, LG, FSG.

On the origin somatotropinoma are the monoclonal tumors developing as a result of vegetative mutation of somatotrof. In 40% by Somatotropinum the mutation of the Gsp-protein providing dimerization and - and ß subunits of G-proteins can be revealed. Somatotropinoma can be a component of a syndrome of multiple endocrine neoplaziya of the 1st type (MEN-1).

Treatment of the Acromegalia:

The purpose of treatment of an acromegalia are elimination of autonomous hyperproduction of a growth hormone, normalization of the IRF-1 level in blood and lack of increase in plasma level of a growth hormone in the glyukozotolerantny test (75 g of glucose) is higher than 1 ng/ml. The specified criteria correspond to remission of a disease.
Choice method at treatment of patients with an acromegalia is removal of adenoma of a hypophysis. At microadenomas growth hormone level after operation is returned to 85% of cases to norm. In case of the small encapsulated adenomas operational treatment, as a rule, leads to permanent remission of a disease. At macroadenomas full treatment after the first operation is reached in 30% of cases. Tumors with ekstrasellyarny growth have the worst forecast.
Somatostatin analogs (октреотид, октреотид long action, ланреотид) allow to normalize levels of a growth hormone and IFR-1 at 50-70% of patients. The sizes of adenoma of a hypophysis decrease less often, only in 30-50% of cases and usually not much more.
Blockers of hormone receptors of growth (pegvisomant) reduce synthesis of IFR-1, competing with an endogenous growth hormone for linkng with his receptor. According to preliminary data at therapy by a pegvisomant the IRF-1 level decreases at 90% of patients. Owing to lack of data on the long-term results of treatment it is used at inefficiency of other methods so far.
Radiation therapy is low effective and can be used as an auxiliary method of treatment. More perspective method is the directed radiation of a residual tumor of ý particles (gamma knife).