Gastrointestinal tract inflammation of atopic diseases children
In structure not infectious diseases of a gastrointestinal tract at children the certain place is occupied with gastrointestinal lesions of an allergic genesis as the digestive tube is not only with an organ through which by an absorption in an organism can inpour various allergens, but also a place of implication of allergic responses at an organism sensibilization inhalation, contact and hematogenous by. Differently, in digestion organs there can be allergic responses as at peroral entering of various antigens (alimentary, medicinal, chemical materials, etc.), and at a parenteral allergization of patients. Symptoms of a lesion of a gastrointestinal tract, a liver, cholic pathes can be observed at a serum disease, a bronchial asthma, pollinoses, an urticaria, a medicinal allergy after injections, etc. In similar cases the digestive tube acts as a "shock" organ and which reaction "antigen-antibody" educes.
All functional disturbances of organs of the digestive tube, bound to the general allergic syndrome, irrespective of entrance hiluses of an antigen, Tsanck named alimentiry, digestive an allergy, unlike an alimentary allergy at which the antigen arrives per os, or food allergy where as an antigen foodstuff acts. The lesion of organs of digestion at the general allergic syndromes speaks bracing of the conforming antibodies in this or that organ of a digestive tube, thus various organs suffer completely not simultaneously and not in parallel. It is characteristic, that out of an allergic attack neither functional, nor organic disturbances in the alimentary system it is not taped. Allergic lesions of a gastrointestinal tract (an abdominal pain, diarrhoeia and other symptoms) are more often observed at children in view of its raised functional lability at this age.
To differentiate disturbances of allergic character from a digestive tube from organic diseases of this or that organ far not always it is easy, as they can proceed as "acute abdomen", intestinal impassability or a clottage of pots of a mesentery. At the expressed general allergic symptoms (an urticaria, a dermal itch, a Quincke's edema, etc.) diagnostics of an allergic lesion of a digestive tube is facilitated. The suspicion on allergic character of disease of a digestive tube arises in cases of paroxysmal appearance of symptoms, their brevity, full well-being and absence of any pathological signs in the season between attacks, in the presence of predisposition of the given patient or its relatives to allergic sufferings of other organs and systems.
Food allergy
The food allergy educes basically on three types of allergic responses: immediate anaphylactic, immunocomplex and slowed down, T-cellular. Apparently, can educe and cytotoxic reactions.
Certain preconditions are necessary for food allergy development. First, presence to it a genetic predisposition. Last is realised in formations of an allergic phenotype. Accurate communication between a food allergy and HLA antigens it is not taped, it is visible because of heterogeneity of its forms, but frequency of antigen HLA-B8, DW3 is raised, as well as at other atopies.
The big frequency of development of a food allergy at children and, especially, at children of early age is bound to insufficiency of barrier function of a gastrointestinal tract, its caused morfo-functional and immune immaturity. Nonspecific, natural, protective mechanisms provide functioning of several barriers: anatomical, physiological, other factors of nonspecific protection. The first barrier on a path of allergens - an epithelium mucous which participates in cavitary and parietal digestion. The diseases breaking integrity of an epithelium and (or) synthesis of digestive juices and enzymes, promote food allergy formation. The physiological peristalsis of an intestine promotes elimination of microorganisms, reduces possibility of their adhesion by an epithelium.
Also it is proved, that in formation of a pathology of a gastrointestinal tract both at children, and at adults disturbances of activity of valval structures of system of a digestive tube matter. "Digestive tube valves" perceive the anatomo-physiological formations located on border of interfacing parts of a digestive tube the term, having various indicators of an internal environment (pH, intracavitary pressure, fermental and bacteriemic structure of medium etc.), functionally referred on maintenance of an optimum homeostasis of a gastrointestinal tract. Valves play a role in maintenance of a constance of various properties of interfacing parts of a digestive tube, promoting autonomy and continuity of activity of each of these parts.
Pathogenetically disturbances of activity of valves of a digestive tube pass consistently some stages. In the beginning - as a result dysregulation digestive tube activity in the answer the enhanced functioning of a muscular part of the valve (tonus rising) educes. This stage is short-term and reversible. As a result of disturbance of processes of acclimatisation, an incoordination of control of valval structure at remaining influences insufficiency of valval structure which in turn passes in two stages gradually educes: at first - functional, and then and anatomical, i.e. full abaissement of function of valval structure on border of two interfacing parts of the digestive tube having various biological characteristics of an internal environment.
All diseases anyhow breaking normal process of digestion, intestine function, help food allergy development. Other kinds of an allergy can be its basis also: medicinal, household, fungoid, chemical, bacteriemic, an autoallergy. Sometimes in the beginning the "alimentiry" allergy (gastrointestinal tract - a shock organ), then true alimentary thus educes.
There is also a close connection between autoimmune reactions, an infectious allergy both immunodeficient, on the one hand, and a food allergy - with another. In one cases these diseases promote an alimentary sensibilization, in others, on the contrary, is long a persistent food allergy conducts to their occurrence. Examples and immediate mechanisms of such communications are diverse. Deficiency Ig And and other factors of immunodefence - a basis for food allergy development, flow and which treatment variate properties and structure of an intestinal microflora that conducts to the dysbacterioses promoting development of antibacterial and autoimmune reactions. Presence of the general antigens between an intestinal rod and a colon epithelium causes an autoserotherapy and occurrence, for example, an ulcerative colitis.
Infection contaminations and autoimmune reactions can lead to occurrence of secondary immunodeficiences, a disbalance of aboriginal factors of immunodefence, depression suppressor mechanisms, hyperproduction Ig E and to deficiency secretory IgА
Specific reactions of elimination
Specific reactions of elimination of alimentary antigens can be the general and aboriginal. Specificity define T - both bursacytes and antibodies of various classes of immunoglobulins which, contacting other leucocytes, involve them in the immune answer.
In norm mucous an intestine permeable even for beta-lactalbumin the cow milk. Are taped and circulating antibodies to some alimentary antigens, and also cell-bound immune complexes, however an allergic response does not educe. However, at a pathology permeability strengthens, that induces qualitatively other answer. There are natural mechanisms of tolerance to alimentary antigens which are broken in the conditions of formation of the allergic status. This tolerance is provided with specific and nonspecific suppressor mechanisms in which participate T - and In - the suppressors, circulating cell-bound immune complexes and serumal suppressor factors. At healthy for cell-bound immune complexes are found Ig And, and at a food allergy - IgE and Ig G, that specifies in change in an immunoregulation. Complexes C Ig A quickly eliminates and if the immune answer is variated and are formed antibodies of classes Ig E and Ig G there is a tolerance break.
Development of system tolerance is promoted by aboriginal tolerance in which development the important role belongs secretory Ig A. At persons with its deficiency high frequency of allergic and autoimmune diseases of an intestine is noted. Secretory Ig A along with others, including the nonspecific. Factors protects an epithelium mucous, prevents attachment to it of microbes. Antibodies Ig A quench receptor moleculas on their surface, will neutralise toxins and viruses, but do not bind thus a complement. Mucous an intestine it is rich with lymphoid cells and other leucocytes, including mast cells (on 1 cubic mm. Their 10-20 thousand, in a skin of-7 thousand). The adenoid tissue Great bulk is in solitary follicles and Peyer's glands, participating in formation of aboriginal immunodefence. Lymphoid follicles are covered by an epithelium, in which many specialised M-cages (membranous). They, probably, are the macrophages transferring an antigen to lymphocytes. Intraepithelial are located T-suppressor (cytotoxic) lymphocytes and particulate t-helper (them much in follicles). Plasmocytes surround cryptas and 82 % produce Ig A, in 16 %-Ig M, in 2 %-Ig G. In a stomach the interrelation of the plasmocytes cosecreting Ig A, Ig M, Ig G, compounds 60:5:3, and in a small bowel 22:3:1. The intestine secret contains much Ig A, synthesised a locally though the part can arrive from blood, especially at an inflammation. Own production Ig A in mucous the child begins to the extremity of 1st month of life. The cells synthesising Ig E, in norm in mucous it is not enough. Their greatest quantity is in a mucous colon.
Anaphylactic type of reaction
The anaphylactic type of reaction educes, when under the influence of the various causes is broken aboriginal and (or) the general tolerance to alimentary antigens in connection with deficiency Ig A, suppressors T-and B, and a monocytic type. Population atopics reacts to antigens the raised synthesis Ig E and Ig G4 antibodies.
At stimulation by various antigens in connection with aboriginal deficiency Ig A and other disturbances of an immunoregulation the quantity of arriving unusual antigens, synthesis of antibodies of other classes, for example Ig E and Ig G which do not carry the functions inherent Ig A is enlarged; in a lumen of an intestine they degrade under the influence of enzymes, and contacting mast cells in a mucosa, cause their sensibilization. These mast cells at the expense of antibodies of class Ig E and some subclasses Ig G co-operate with the conforming allergens of nutrition repeatedly inpouring in mucous intestine, excreting allergic response mediators.
Allergy mediators cause the basic usual effects: reduction of a smooth musculation, a phlegm hypersecretion, rising of permeability and a paresis of fine pots. In an intestine it shows a colic, a diarrhoeia with a mucous chair and other symptoms.
The important part of a pathogenesis of a food allergy - its relapsing flow. The primary sensibilization at a repeated occurring with an alimentary antigen is authorised an allergic response which degree strengthens at new contacts to the same allergen. It forms a basis of clinical exacerbations of a food allergy, giving to it lingering and chronic character.
Immunocomplex reactions
Immunocomplex reactions (3 type) educe in 6-12 hours or some days after food intake. A basis of their mechanism-formation of cell-bound immune complexes by antibodies of class Ig G 1, Ig G 2 and Ig G 3 or Ig M, binding a complement, which products of activation induce development of vasculites. Probably, therefore there can be intestinal bleedings at children till 2th years, a hemosiderosis of lungs and a lesion of nephroses. Sometimes the clinical exacerbation coincides with lifting in blood of level Ig E - keeping cell-bound immune complexes. Cell-bound immune complexes can be found in the form of deposits in the struck organs.
The slowed down T-cellular type
The slowed down T-cellular type of an allergy educes in 1-3 days after introduction of allergen and is accompanied by infiltration of places of entering of allergen by mononuclear cells. At repeated receptions of allergenic nutrition process becomes chronic. It is revealed, that alimentary additives cause MYTH-FACTOR development (that is a mediator hypersensitivity of the slowed down type) at stimulation of lymphocytes in patients with a chronic urticaria a tartrazine, aspirin, Sodium benzoatum. Hence, alimentary additives too can induce hypersensitivity of the slowed down type.
Proofs of development of cytotoxic reaction (2 type) at a food allergy practically are not present. However, as it is quite often accompanied hemolitic, thrombocytopenic and leukopenic reactions, it is possible to assume, that on a surface of blood cells can sorb the conforming antigens and to induce these reactions, involving antibodies of class Ig G and activating a complement. Besides, the cells of an epithelium deprived of protection at deficiency Ig A, can sorb antigens of nutrition and through them to co-operate with antibodies. With a complex arising on their surface an antigen a-antibody various leucocytes (neutrophils, cytotoxic B lymphocytes, etc.) will co-operate and to damage them (antibody-dependent cytotoxicity).
The admixed reactions
The admixed reactions (for example, 1 and 3 type, 3 and 4 type), apparently, too meet at hypersensitivity to nutrition.
Along with the listed types of allergic responses at an alimentary and "alimentary" allergy other variants of retseptorno-metabolic reactions (5 type) should be observed. Antibodies can quench receptors on a hormone producing cells or target cells for neurotransmitters, to bind interspinal hormones, thereby breaking normal function of an intestine, causing intensifying of production of the vasoactive peptides inducing a vasodilatation, augmentation of permeability of pots, a hypersecretion, peristalsis intensifying, i.e. allergic response symptoms. Obviously, production of hormones and intestine neurotransmitters sharply variates and at classical types of an allergy. Besides, the excitatory stimulation promotes abjection of neuropeptids which are capable to induce degranulate of mast cells immediately. Now leading value of foodstuff is proved at respiratory allergoses, however the role of household and pollen allergens till now is not clear at allergic lesions of a gastrointestinal tract. At the same time there is a concept, formulated F.Liberman and L.Crawford, that inhalation allergens, inpouring into an organism through respiratory tracts, can reach cells of any organ including a gastrointestinal tract, with the subsequent formation specific reagin, their bracing by the receptor apparatus of mastocytes and histic basophils and occurrence of immune conflicts allergen-antibody, remission of biologically active materials. The last cause spastic and vasosecretory the disorders underlying clinical implications of gastrointestinal allergoses.
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