D3.384 - PREVALENCE OF SENSITIZATION TO PANALLERGENS AND IgG4 PROFILES AGAINST SPECIFIC FOODS IN PATIENTS WITH EOSINOPHILIC ESOPHAGITIS OF ALLERGIC PHENOTYPE

Eosinophilic esophagitis (EoE) is an inflammatory process that affects the esophageal mucosa and deeper layers of the esophagus. Its pathophysiological mechanism is complex and it´s still being investigated. Different EoE phenotypes (allergic or non-allergic) with different histopathological patterns (inflammatory with or without stenosis) have been described to date, and both can be observed simultaneously.

Our hypothesis is that by performing blood analysis for detection of total IgE, specific IgE against food and aeroallergens, specific IgG4 against food and molecular diagnosis, IMMUNOCAP ISAC ® for the detection of allergenic triggers, we will objectify a high prevalence of sensitization to aeroallergens, foods and panallergens, with statistically significant differences compared to the control groups without EoE. We expect to objectify a high prevalence of this kind of sensitization in allergic phenotype EoE patients versus non allergic ones.

We have measured the prevalence of sensitization to aeroallergens, foods and panallergens by means of molecular diagnostic techniques and determined the levels of specific IgG4 against foods and eosinophilic derived neurotoxin (EDN) in patients with EoE of allergic phenotype and to study if there are statistically significant differences with respect to the control groups (patients with allergic typical/immediate food exclusively IgE-mediated without EoE, patients with non-food allergy, preferably with aeroallergen sensitivities without EoE, and healthy patients without documented allergies).

The total number of patients under study is 120, distributed among the different study groups. The case group has 50 subjects. The food and respiratory allergy control groups, 30 subjects each. Finally, we included 10 in the healthy control group.

Currently we can offer preliminary data with a total number of 55 patients. The results indicate that there are striking differences in the levels of IgG4 in the group of patients with eosinophilic esophagitis compared to the control groups, being specially prevalent egg white, casein or wheat. Likewise, the prevalence of sensitization to panallergens is very notable in the case group compared to the control groups. However, and despite there being many subjects left to analyze, we have not found notable differences in EDN levels between the different groups.

The results obtained seem to confirm that in patients with EoE of an atopic profile, high levels of IgG4 are observed against certain foods as well as a high prevalence of sensitization to panallergens, compared with the control groups. We must complete the study with all patients to confirm these data and their clinical implications.