Hypophysial nanizm – an endocrine disease which cornerstone violation of synthesis of hormone of growth (somatotropin) in a forward share of a hypophysis is that leads to a growth inhibition of a skeleton, internals and a physical underdevelopment. The hypophysial nanizm is characterized by abnormal low-tallness: growth of men is lower than 130 cm, growth of women is lower than 120 cm; lag in development of bone and muscular system, a gipogonadizm, reduction of the sizes of internals, hypotension, bradycardia, etc. is noted. Diagnostics of a hypophysial nanizm assumes definition of basal concentration of STG in blood serum, conducting pharmacological tests, a X-ray analysis of a skull, hands and luchezapyastny joints. Treatment of a hypophysial nanizm includes replacement therapy somatotropiny, anabolic steroids, tireoidny medicines, sex hormones.
Concept the nanizm (a mikrosomiya, a nanosomiya, dwarfism) is designated in a broad sense by a number of the pathological states which are expressed in lag of growth and physical development in comparison with average age, sexual, population and racial norm. Nanizm can be an independent genetic disease or act as a symptom of a number of endocrine and not endocrine diseases.
Distinguish a nanizm with a proportional and disproportionate constitution. With a proportional constitution carry a hypophysial nanizm to group of diseases; miksedematozny (tireogenny) nanizm; a nadpochechnikovy nanizm at an adrenogenital syndrome (a congenital giperplaziya of adrenal glands); the nanizm connected with damage of a thymus; the infantile nanizm developing under the influence of exogenous factors (alimentary insufficiency or intoxication); the nanizm connected with premature puberty and early closing of zones of growth. Nanizm with a disproportionate constitution is presented by the following forms: rachitic, hondrodistrofichesky, dwarfism at imperfect osteogenesis (congenital fragility of bones). It is necessary to distinguish family (constitutional) forms of low-tallness which are considered as option of individual physical development from cases of a nanizm and are not pathology.
Hypophysial nanizm – the clinical syndrome caused by absolute or relative somatotropny insufficiency of a hypophysis (a lack of secretion of somatotropny hormone or violation of fabric sensitivity to it). The hypophysial nanizm meets in population frequency of 1:15 000 - 1:20 000, is slightly more often among men.
Reasons of a hypophysial nanizm
The Somatotropny insufficiency which is the cornerstone of a hypophysial nanizm can be caused by three groups of the reasons: the congenital deficiency of somatotropny hormone (STG) acquired by a giposomatotropny condition and peripheral resistance of fabrics to influence of STG. Congenital insufficiency of a somatotropin can be connected with genetic defects (growth hormone gene mutation, a receptor gene mutation to a somatoliberin, etc.) or anomalies of development of gipotalamo-hypophysial system (an anentsefaliy, congenital aplaziya, a hypoplasia or an ektopiya of a hypophysis).
The acquired hypophysial nanizm develops at tumors of gipotalamo-hypophysial area (a kraniofaringioma, a gamartoma, neurofibroma, a germinoma, hypophysis adenoma) or tumors of other departments of a brain (for example, a glioma of a visual recross). In certain cases can lead craniocereberal injuries, patrimonial injuries, neuroinfections (viral, bacterial encephalitis and meningitis) to a hypophysial nanizm, autoimmune gipofizit, injury of a leg of a hypophysis at surgical interventions, hydrocephaly, aneurisms of vessels of a hypophysis etc. The hypophysial nanizm can be connected with toxic consequences of chemotherapy or radiation (at leukemia, a retinoblastoma, bone marrow transplantation etc.).
The hypophysial nanizm owing to tolerance of fabrics targets to hormone of growth can develop at deficiency of STG-receptors, lack of biological activity of somatotropny hormone, resistance to an insulinopodobny factor of growth 1.
Along with the isolated insufficiency of STG, at a hypophysial nanizm decrease in synthesis of other hormones of a hypophysis can be noted: gonadotrophins, TTG, AKTG that is followed by insufficiency of function of the corresponding peripheral endocrine glands (sexual, thyroid, adrenal glands) that also influences growth and physical development. In this case in endocrinology speak about a pangipopituitarny form of dwarfism.
Symptoms of a hypophysial nanizm
Children are born with normal veso-growth indicators. The growth inhibition at a congenital hypophysial nanizm becomes usually noticeable to age of 2-3 years and further accrues. Growth rate at children with a hypophysial nanizm makes 1,5-2 cm a year (at norm – 7-8 cm). At adult men growth does not exceed 130 cm, women have 120 cm. The constitution is proportional, however the proportions peculiar to children's age can remain.
Integuments at patients with a hypophysial nanizm pale, dry, wrinkled, with a yellowish or marble shade that is caused by tireoidny insufficiency. Head hair often thin, dry, fragile. The underdevelopment of bones of a facial skull causes existence of small features ("the doll person"), zapadeny nose bridges.
Distribution of hypodermic and fatty cellulose can be various – from poor development before excess adjournment of fat on "kushingoidny" type (on a breast, a stomach, hips). The delay of ossification of a skeleton, poor development of muscular system, violation of change of teeth is noted. Because of a throat underdevelopment at adults with a hypophysial nanizm the high children's timbre of a voice remains. According to the low growth and body weight reduction of the sizes of internals is noted (splankhnomikriya). Quite often at a hypophysial nanizm bradycardia and arterial hypotension comes to light.
Violation of gonadotropny function of a hypophysis leads to a delay and inferiority of sexual development (gipogonadizm). At young men with a hypophysial nanizm lack of pilosis on men's type, a hypoplasia of testicles, a kriptorkhizm, a micropenis is observed; at girls - , a mikromastiya, a hypoplasia of a uterus and ovaries.
Intellectual development at a hypophysial nanizm, as a rule, sokhranno. Such psychological features as negativism, isolation, decrease in a self-assessment, infantile behavior can be noted. In the presence of additional complaints to a headache, vomiting, violation of sight it is necessary to suspect intra cranial pathology. At a pangipopituitarny nanizm signs of a secondary gipokortitsizm and a hypothyroidism are defined.
Diagnostics of a hypophysial nanizm
As criteria of diagnostics of a hypophysial nanizm serve data of the anamnesis, objective inspection, laboratory and tool researches. At patients the absolute sizes of a body, and also an indicator of deficiency of growth – a difference between the actual growth of the patient and average standard gender and age values in population are defined. At a hypophysial nanizm deficiency of growth makes more than 2-3 square deviations.
The main role at diagnostics of a hypophysial nanizm belongs to determination of the STG basal level in serum of blood, a circadian rhythm of secretion and reserves against the background of stimulation. At patients with a hypophysial nanizm the STG initial level is considerably reduced, when carrying out the stimulating tests with insulin, tireoliberiny, argininy, etc. increases slightly.
The X-ray analysis of the Turkish saddle reveals its children's form ("a standing oval") and wide (so-called juvenile) a back. At increase in the sizes of the Turkish saddle and existence of sites of calcification, first of all, it is necessary to think of a tumor. The X-ray analysis of luchezapyastny joints and brushes allows to define radiological ("bone") age. At a hypophysial nanizm considerable delay of processes of ossification of a skeleton is noted.
Clarification of a form of a nanizm requires a research of an insulinopodobny factor of growth (Somatomedina-c), TTG, LG, FSG, T3, T4, cortisol in plasma and urine, antibodies to a tireoglobulin, mikrosomalny fraction of tirotsit, etc. For an exception of tumoral defeat brain KT (MPT) is carried out.
At a hypophysial nanizm the patient has to be consulted by the endocrinologist, the gynecologist (woman), the andrologist (man), the neurologist or the neurosurgeon, the ophthalmologist, the geneticist.
Treatment of a hypophysial nanizm
At children of younger age for an exception of diagnostic mistakes for 6-12 months maintain the period of observation during which special attention is paid to good nutrition, the all-strengthening therapy, reception of vitamins (And yes D) and minerals (phosphorus, calcium). Lack of dynamics of growth and physical development is the basis for transition to hormonal therapy.
The basis of pathogenetic treatment of a hypophysial nanizm is made by replacement therapy by growth hormone medicines which is carried out by faltering courses (2-3 months with the same intervals). Somatotropin of the person is appointed to patients with the proved endogenous insufficiency of hormone and the differentiation of a skeleton which is not exceeding age indicators of 13-14 years. Treatment by means of STG is carried out before closing of zones of growth or before achievement of the acceptable growth parameters.
In therapy of a hypophysial nanizm the anabolic steroids (, ) having the stimulating effect on the level of endogenous STG, synthesis of proteins and growth are applied. Treatment by steroid hormones continues several years with periodic replacement of medicines. It is expedient to begin treatment with anabolic means from 5-7 years. For stimulation of function of gonads 16 years to young men are aged more senior the horionichesky gonadotrophin and small doses of androgens, to girls - small doses of estrogen is appointed.
Further, after closing of zones of growth, patients with a hypophysial nanizm are transferred to constant reception of sex hormones in compliance a sex. At the same time to women reception of the combined estrogengestagenny medicines is shown, to men - androgens of the prolonged action.
At a gipoterioza L-tiroksin, is appointed; at insufficiency of a somatoliberin - its synthetic analogs; at hypofunction of bark of adrenal glands - glucocorticosteroids. At organic pathology of TsNS anti-inflammatory, rassasyvayushchy, dehydrational therapy can be required. In case of detection of tumors of a hypophysis their surgical removal, sometimes – performing radiation therapy is shown.
Forecast and prevention of a hypophysial nanizm
At the hypophysial nanizm caused by the genetic reasons, the forecast good. Timely and rational ZGT allows patients to be sufficiently physically developed, socially active and able-bodied. At choice of profession the work providing the raised physical and psychological activities is not recommended. In the absence of necessary treatment patients have small growth and a physical underdevelopment. In case of organic damages of a brain the forecast is defined by the main disease and dynamics of its development. Patients with a hypophysial nanizm are on the lifelong dispensary account at the endocrinologist and each 2-3 months have to visit him.
Prevention of a hypophysial nanizm consists in the prevention of infections, physical and mental injuries at pregnant women; prevention of patrimonial injuries, neuroinfections, ChMT, intoxications at children.