The first dissertation with molecular allergology background in Georgia was defended on 12th of December, 2017 by Nino Lomidze (former active member of EAACI Junior board and the member of INUNIMAI) in Tbilisi State Medical University. The title of the thesis was: “Epidemiological Markers of IgE-Mediated Food Allergy in Allergic Patients”. Scientific consultant - Prof. Maia Gotua MD, PhD (Coordinator of INUNIMAI in Georgia).
The aim of the first part of the study was to report the prevalence of self-reported food allergy in the different age groups of Georgian population and to reveal the most common self-reported food allergens. ISAAC (International Study of Asthma and Allergy in Childhood) phase III study methodology and questionnaires were used for data collection. Questions about self-reported food allergy were added to the survey and analyzed. 6/7 years old 6140 children (response rate-94,5%) and 13/14 years old 5373 adolescents (response rate-86,9%) from two locations of Georgia, Tbilisi and Kutaisi were surveyed. 500 randomly assessed adults from Tbilisi aged 18 years and older were added later (response rate-97,6%). While some studies on food allergy have been conducted so far, this is the first time its prevalence has been investigated in different age groups of Georgian population.
Findings revealed that self-reported food allergy prevalence among 6/7 years old age group and 13/14 years old age were almost the same (15,7% and 15,9% correspondingly) and slightly lower in adult population - 13,9%. Study revealed, that hen’s egg was the commonest implicated food allergen for 6/7 years age group, hazel nut – for 13/14 yrs. old age group followed by hen’s egg. Walnut and hazel nut were most reported food allergens for adult population. The findings also revealed that food allergy is one of the most important risk factor for symptoms associated with asthma (OR-3,05; 95%CI 2.50-3.74), rhinoconjunctivitis (OR-2,85; 95%CI 2.24-3.64) and eczema (OR-5,42; 95%CI 4.08-7.18) in childhood.
The aim of the second part of our study was to investigate sensitization pattern to food allergens in the different age groups of atopic patients in Georgia and reveal the associations between food sensitization and clinical manifestations of allergic disease reflecting the development of atopic march. 1000 patients (children-783, adult-217) with different clinical manifestations were involved in this study. Specific IgE antibodies to food mix, cow’s milk, casein, egg, wheat, fish, nuts mixture and inhalant allergens were measured by using ImmunoCap (Thermo Scientific, USA). The prevalence of positive specific IgE to food mix (egg white, milk, fish, wheat, peanut, soybean) was - 7.08%, cow’s milk-4.61%, casein - 4.68%, hen’s egg - 2.72%, fish mix (shrimp, blue mussel, tuna, salmon) - 0.77%, wheat -1.57% and to nuts mixture (peanut, hazel nut, brazil nut, almond, coconut) - 2.86%. Allergic skin manifestations to ingested food were age-dependent, more frequent in children groups. Atopic dermatitis was the most common disease of childhood (64% of <2 yrs age group), but its frequency was significantly decreased with age. Cow’s milk and hen’s egg were the commonest food allergens in the age group of <2 years. All the patients in presented study outgrow allergies to cow’s milk and hen’s egg during school age. Sensitization to food mix, cow’s milk, casein, hen’s egg and wheat were predominated in male patients. Egg allergy was significantly associated with atopic dermatitis, fish allergy to bronchial asthma and severe milk allergy to anaphylactic shock.
The aim of the third part of our study was to investigate sensitization patterns to food components in the most atopic patients. CRD investigation was done in 146 patients, 60 adults (mean age 36.6 ±11.8) and 86 children (mean age 6.7±4.6). Allergic patient’s sera samples were tested by a microarray technology (ImmunoCap ISAC, Thermo Fisher Scientific, ImmunoDiagnostics, USA) and specific IgE levels against 112 different allergen components were detected. 29.5% were ISAC negative and were excluded from the study.
Among investigated mainly specific IgE to nGal d 1 (11.20%), nBos d 8 (11.20%), rJur1 (12.90%), rJur 2 (15.5%) were more prevalent. Sensitization to Bos d 8, Gal d 1, rJur1, rJur1 were predictors of allergy persistence in later life and association with systemic reactions. Children with severe allergic reaction should be checked attentively every six month and their dietary modifications and quality of life should be regularly assessed. In case of occasional contact with food allergens individual action plan against anaphylaxis should be followed, including using of epinephrine auto injector. 6.3% of milk allergic patients were sensitized to nBos d 6 (cow’s milk/meat components) and 1.2% of patients allergic to egg were sensitized to Livetin (Egg yolk/chicken meat component). Patients with high IgE levels of to nBos d 6 and Livetin should be given a recommendation to be careful with cow’s and chicken’s meat, because there is a risk of developing allergic reaction to them as well.
Present study is the first comprehensive investigation that provides unique data of the prevalence of food allergies in Georgian population. The results of this study are contributing to a better understanding of the food allergy, serving as a basis for the development of strategies for preventing and treating food allergies.