DEFINITION OF SENSITIZATION TO POLLEN ALLERGENS WORMWOOD AND HAZEL IN PATIENTS WITH RESPIRATORY ALLERGIC DISEASES BY IMMUNOBLOT AND MULTIPLEX COMPONENT TEST

Specific diagnosis of respiratory allergic diseases is an indispensable component of allergology, which must be used at the stage of diagnostic search in a patient with allergopathology [1-3]. The place of each of these methods in the patient’s itinerary, however, is being actively discussed with the advent of new and new methods available for routine practice [4,5]. The aim of our study was to evaluate the diagnostic parameters of immunoblot and Immunocap ISAC methods to determine allergic sensitization to wormwood and hazel in patients with respiratory allergic diseases – allergic rhinitis and bronchial asthma.

In the main phase of the study 40 people aged 19-42 years were selected, the average age of the group was 31.6 years (95% CI: 26.6; 41.6), gender distribution -60.0% of men and 40.0% of women.
Among the patients, allergic sensitization to wormwood was 27.5% (11 people) by the presen ce of specific IgE by the Rida AllergyScreen, 25.0% (10 people) by the presence of specific IgE by the I m-munoCAP ISAC; sensitization to hazel allergen was 27.5% (11 people) by the presence of specific IgE by the Rida AllergyScreen, 30.0% (12 people) by the presence of specific IgE by the ImmunoCAP ISAC. Table 1 shows the results of constructing the affinity table of the results of determining specific IgE to wormwood.  Table 2 shows the results of constructing the affinity table for the determination of specific IgE to hazel. The expected frequency of the sign in one of the cells (25%) of the summary tables below is 5 and we used the Fisher exact two-way criterion method to analyze the relationship. As a result of statistical data processing, it is determined that the absolute value of the exact two-sided Fisher criterion for the wormwood allergen corresponds to the two-sided asymptotic significance of 0.024, which accepts the null hypothesis. At such levels of asymptotic significance, the difference between the measurement groups is the null hypothesis, and, therefore, no statistically significant difference was found between survey methods for the determination of specific IgE for allergen wormwood.
In the case of hazel allergy sensitization by two different methods, the expected symptom frequency in one of the cells (25%) of the summary tables below 5 was also applied to analyze the relationship of the Fisher exact two-sided criterion. As a result of the statistical data processing, it is determined that the a bsolute value of the Fisher's exact two-sided criterion for hazel allergen corresponds to a two-sided asymptotic significance of 0.001, which rejects the null hypothesis. At such levels of asymptotic significance, the difference between the measurement groups is null and void, and therefore a statistically significant difference was found between survey methods for the determination of specific hazelnut IgE.
For a complete analysis of the diagnostic parameters of the methods we calculated the sensitivity, specificity, accuracy, positive and negative predicitive value of the immunoblot against ImmunoCap ISAC. The results of these parameters for birch allergen are shown in table 3. Sensitivity is the ability of the diagnostic method to produce the correct result, which is defined as the proportion of true positive results among all tests performed. Specificity is the ability of the diagnostic m ethod not to give in the absence of the disease false positive results, which is defined as the proportion of true negative results among healthy individuals in the group of subjects. Therefore, immunoblotting for the determination of specific IgE for allergen wormwood compared to Immunocap ISAC is highly sensitive, highly specific and highly accurate. Special attention should be paid to the positive predicitive value, which is defined as the percentage of true positive tests among all positive tests obtained as a result of the examination. In this case, it was 90.91%, which indicates the possibility of a false positive result in every tenth case. The results of these parameters for hazelnut allergen are given in table. 4. As we can see, immunoblot compared to ISAC for the determination of specific hazards of hazel alle rgen has a relatively high specificity and negative predictive value (92.86% and 89,66%), but the sensitivity and positive predicitive value have a value of 75.00% (95 % CI: 42.81; 94.51) and 81.82% (95% CI: 53.23; 94.68), respectively, and the accuracy of the method is 87.50% (95% CI: 73.20; 95.81).
Therefore, the immunoblotting method for the determination of specific IgE for hazel allergen compared to Immunocap ISAC is highly specific, but medium-sensitive. Special attention should be paid to the predictability of negative and positive results, which amounted to 89.66% and 75.00%, which indicates a significant possibility of false negative and false positive result.

Discussion
The higher the sensitivity of the test, the more often it will detect the disease, so it is mo re effective. At the same time, if such a highly sensitive test proves negative, then the presence of the disease is unlikely. Therefore, they should be used to exclude diseases. Because of this, highly sensitive methods are often called identifiers, and it is recommended to use them in the early stages of the diagnostic process, when you need to narrow down the range of suspected diseases. On the other hand, the higher the specificity of the method, the more reliable it is to confirm the disease, and therefore, it is more effective. Highly specific methods are called discriminators in diagnosis. Such studies are effective in the second stage of diagn osis, when the range of suspected diseases is narrowed and it is necessary to prove with great certainty the presence of the disease.
The results of the analysis showed high sensitivity, specificity and accuracy of immunoblotting for the determination of IgE specific for allergen wormwood compared to Immunocap ISAC, as well as high spec ificity, moderate sensitivity and accuracy for determination of specific IgE for the allergen of hazel.
In our opinion, there may be a number of factors that may cause such differences. The main point is that the increase in the sensitivity of the test is inevitably accompanied by the loss of its specificity, and vice versa, the increase in specificity is associated with a decrease in its sensitivity. Diagnosis techniques with high sensitivity rarely «miss» patients who have the disease, and techniques with high specificity do not qualify as healthy patients. On the other hand, the reduced sensitivity of the method may be directly related to the immunoblotting technique itself, since photometric analysis depends in practice on many factorsthe quality of the scan, the correct preparation procedures, the presence or absence of calibration, and the like.
The negative predicitive value is defined as the frequency of its coincidence with the absence of the disease. This criterion thus shows how likely the patient is to be healthy if the results of the study are negative. In our case, the negative predictive value for the immunoblot method is generally related to the se nsitivity of the method.
Ключевые слова: аллергия, имуноблотинг, IgE, молекулярная аллергология. The aim of our study was to evaluate the diagnostic parameters of immunoblot and Immunocap ISAC methods to determine allergic sensitization to wormwood and hazel in patients with respiratory allergic diseasesallergic rhinitis and bronchial asthma.