CLINICAL AND LABORATORY ASPECTS OF DETECTING SPECIFIC IgE ANTIBODIES TO COW’S MILK AND ITS COMPONENTS

Food allergy against cow milk and its components is highly prevalent among infants and children of pre-school and young school age being a sufficient factor influencing health condition of children during the maturation period. Clinical signs of the milk allergy are non-specific, and they may be pronounced or expressed in mild form, thus enabling hypodiagnistics of this disorder. Moreover, a variety of milk antigens determines different clinical course of this allergic condition and brings additional difficulties to its diagnostics and treatment. Meanwhile, a sensibilization for the cow milk proteins may sometimes trigger a generalized atopy and bronchial asthma, being a factor delayed growth and other health disorders. At the present time, there are no distinct risk criteria for milk allergy. Therefore, its successful prophylaxis and treatment largely depends on the competence of clinical allergologist and informativity of the diagnostic techniques used. So far, however, we have no generally approved laboratory algorithms for diagnostics and monitoring of treatment efficiency in the cow milk allergy and its compomemts.We have performed a laboratory study of 187 children at the age of 3 months to 10 years. An immunochemoluminescent assay of specific IgE antibody levels to the cow milk using IMMULITE 2000/XPi analyzer has revealed its good informative value at different approaches to prediction and evaluation of food allergy treatment, both oriented for a critical cutoff value of 3 МU/L, and by monitoring a decrease in antibody levels. The authors consider rational an extended indefinity principle during the patient-oriented interpretation of IgE assay results if clinical decision is based on critical value of the index. In cases of clinical monitoring, the limit of interim reproducibility should be taken into account. The prevalence of specific cow milk antibodies among the boys was higher than among girls, however, with lesser frequency of moderate/high reactivity among the males. Moreover. the cases were detected with higher levels of anti-beta-lactalbumin IgG than those against whole milk. This finding should be considered during the screening studies.On the basis of literature analysis and own results, the authors propose an extensive study of specific IgE antibodies against cow milk and its components in blood serum of infants and children form the pre-school and junior school age groups

Studying informativity of specific IgE levels to whole cow milk allergen and its components, as well as to soy and gluten in children

Successive development of immunological tolerance to cow’s milk proteins largely depends on the timeliness and validity of the elimination diet and is most difficult in IgE-mediated food allergy. From 2012 to 2017, when examining children aged 3 months to 10 years, we found some cases with high levels of specific IgE to beta-lactoglobulin that exceeded the levels of specific IgE to the whole cow’s milk allergen (the latter is often used as a screening allergen). The aim of this study was to assess the informativity of studying the levels of specific IgE to the whole cow’s milk allergens in blood serum of children at early, preschool and primary school age. We have also included gluten (gluten) and soy as possible components of early childhood nutrition into the list of allergens under study. The study involved 100 children aged 9 months to 12 years. Clinical selection criteria included presence of anamnestic data on exacerbation of atopic dermatitis, urticaria, exacerbation of rhinitis/asthma, diarrhea, constipation or abdominal pain in response to usage of cow’s milk and/or dairy products during the last 6 months. It is shown that extended study of specific IgE levels to whole cow’s milk allergen, its components, as well as to soy and gluten, increases the accuracy of laboratory diagnostics and differential diagnosis of IgEmediated form of food allergy to cow’s milk proteins, compared with determination of serum IgE to whole cow’s milk as a screening test. A detailed study of specific IgE to milk components allowed to confirm the presence of IgE-mediated form of allergy to cow’s milk in 7% of the examined children with signs of food allergy, but in absence of specific IgE to whole cow’s milk allergen. We have also shown that in 29% of cases, the level of specific IgE to milk components was higher than those to whole cow’s milk allergen. The results of this study may be of practical importance, since the form of food allergy, as well as intensity and dynamics of reduction of production of specific IgE, are accepted criteria to forecast development of tolerance to cow’s milk proteins. In addition, identification of specific allergen (including soy bean allergen) that causes the most intense production of specific IgE, may be importance for administration of a reasonable elimination diet. The most significant allergens for diagnosis and differential diagnostics of allergy to cow’s milk in children, in addition to the “whole cow’s milk, f2” preparation, are the following allergens: “whey, f236”, “beta-lactoglobulin, f77” and “soy, f14”