Allergic gastritis is a clinical variant of food allergy, the main manifestations of which are symptoms of stomach damage. This condition may be the first manifestation of an allergic disease that develops when an antigen enters the stomach directly. It is often combined with intestinal damage and occurs in the form of gastrointestinal allergies, more often develops in childhood. The main etiological factor is cow’s milk proteins, as well as eggs, fish, some fruits, mushrooms. Treatment is based on the appointment of an elimination diet, specific immunotherapy, symptomatic measures.
ICD 10
K52.2 Allergic and alimentary gastroenteritis and colitis
Meaning
Allergic gastritis is an immuno-mediated gastric lesion that serves as a manifestation of hypersensitivity to food. Often the disease is accompanied by the involvement of other organs and systems: in 60% of cases there are also skin symptoms, less often – respiratory manifestations, visceral disorders, hemopathy, extremely rarely – anaphylactic reactions. Due to the large number of potential allergens, the presence of cross, latent allergies, similar symptoms of other diseases of the gastrointestinal tract, accurate verification of the diagnosis is difficult, and therefore hyper- and underdiagnosis takes place. About 65% of patients with allergic pathology indicate food intolerance, but true allergic gastritis occurs in about a third of them. Histologically, the disease is characterized by eosinophilic infiltration of the mucosa and deeper layers, therefore this pathology is also called “eosinophilic gastritis”.
Causes of allergic gastritis
The cause of this pathology is ingestion of food antigens into the stomach. The leading role is played by allergy to cow’s milk proteins, which is determined in 90% of children under a year after being transferred to artificial feeding. Cow’s milk contains up to 20 proteins with a high sensitizing potential. Also powerful allergens are eggs, fish, cereals, some vegetables and fruits, mushrooms.
Often the reaction develops on the additives contained in the products: flavorings, emulsifiers, preservatives. The reason may also be ethylene, an oil product that is used to process unripe fruits. It is proved that allergic gastritis in young children is more often caused by allergens of cow’s milk, in older patients – chocolate, citrus fruits, strawberries.
Sensitization develops not only to food products, but also to allergens of a non-food nature. This is due to cross-allergy caused by the similarity of antigenic determinants of food, plant pollen, household allergens, medicines. For example, cross-allergy between natural latex (nipples, toys, gloves) and avocado, kiwi and other products is quite common.
The development of gastrointestinal allergy is facilitated by factors such as hereditary predisposition to atopy, unfavorable environmental conditions, gestosis in the mother, earlier feeding in children, features of the gastrointestinal mucosa.
The formation of allergic gastritis is closely associated with impaired tolerance to antigens, shifts in local immunity of the gastrointestinal tract and general changes in the immune system, functional digestive disorders due to peptidase deficiency, decreased acidity of gastric juice, impaired gastrointestinal microbiocenosis, excessive release of biogenic amines (histamine, acetylcholine, serotonin).
An important role in the development of gastrointestinal allergies in children is played by improper nutrition of the mother during pregnancy, as well as irrational feeding of the child during the first year of life, including early introduction of complementary foods, feeding with unadapted milk mixtures.
Allergic gastritis symptoms
With this pathology, eosinophilic infiltration is extremely rarely limited to one department of the gastrointestinal tract. The stomach and small intestine are most often involved in the process. The symptoms depend on how deeply the organ wall is infiltrated by eosinophils. If only the mucous membrane is affected, symptoms such as pain in the epigastric region, diarrhea, nausea, vomiting prevail. When the muscle layer is involved, signs of intestinal obstruction (bloating, nausea, vomiting) prevail. Infiltration of the subserous layer is accompanied by the development of ascites, while a large number of eosinophils are detected in the ascitic fluid.
Ingestion of an allergen into the stomach leads to increased motility, increased secretion of the glands of the mucous membrane, spastic contractions of the antrum. Gastroesophageal reflux may develop, with burning sensation, epigastric pain, copious saliva discharge, nausea, vomiting. Vegetative disorders are characteristic: weakness, pallor of the skin, palpitations, dizziness.
Diagnostics
The diagnosis of this pathology is carried out in two directions: assessment of the clinic, laboratory, instrumental studies and dietary diagnostics. An important role in verification is played by determining the relationship between the use of an allergen and the appearance of symptoms. Special attention is paid to the data of food, allergological, pharmacological anamnesis, analysis of the food diary. The degree of damage to the digestive system, a combination with symptoms from other organs, is assessed.
To determine the cause of the disease, specific allergodiagnostics are performed (skin prick tests, assessment of the level of specific IgE, provocative tests). It is mandatory to keep a food diary. The patient notes the products consumed in it, registers the symptoms that have appeared. To determine the etiological factor, an elimination test is carried out. It consists in the fact that potential allergens are excluded from the diet for 1-2 weeks. If there are several suspected products, the sample is carried out sequentially with the exclusion of each of them. The most reliable information is provided by provocative food samples. These methods are carried out no earlier than a month after the disappearance of acute complaints.
To exclude other diseases, as well as to assess the degree of mucosal damage, endoscopic diagnostics is performed with the examination of biopsies. Gastroscopy is performed with simultaneous endoscopic biopsy. Histological examination of the biopsy shows an increase in the content of eosinophils. In the blood test, an increased content of eosinophils is determined against the background of the absence of other changes.
Differential diagnosis of allergic gastritis is carried out with other diseases and abnormalities of the digestive tract (primarily with catarrhal, atrophic and hyperplastic gastritis, gastric ulcer), metabolic disorders, intoxication, infectious, endocrine diseases, immunodeficiency conditions.
Allergic gastritis treatment
The therapy of this disease is carried out by the treating gastroenterologist together with an allergist-immunologist. Methods of treatment of gastrointestinal allergy are divided into specific and nonspecific. Specific methods include the exclusion of a food allergen (the appointment of a specialized diet), as well as ASIT – antigen-specific immunotherapy with the use of food allergens.
Nonspecific pharmacotherapy involves the appointment of antiserotonin drugs, systemic glucocorticosteroids, drugs that prevent the release of biologically active components from mast cells, immunomodulators, as well as drugs that normalize the functions of the gastrointestinal tract: pancreatic enzymes, hepatoprotectors, enterosorbents, probiotics, prebiotics.
Elimination measures involve the complete exclusion of not only the antigen itself, but also products in which it is found even in extremely small quantities. At the same time, the patient should receive nutrition corresponding to energy and nutritional needs. If it is not known which product caused gastritis, empirical elimination diet therapy is carried out – all potential food allergens are excluded.
Prognosis and prevention
The basis for the prevention of gastrointestinal allergy is the prevention of contact with an allergen in early childhood, rational nutrition of women during pregnancy, natural feeding, if it is impossible, the use of adapted mixtures, individual diet preparation in patients with a burdened allergic anamnesis. The prognosis of the disease with adequate treatment, rational nutrition is favorable. Food allergies lose their dominant role with age, but long-term allergic gastritis can cause ulcerative colitis and other immune-mediated diseases.