The study of egg allergy in children with atopic dermatitis

Relationship Between Atopic Dermatitis and Food Allergy in Children

Atopic dermatitis (AD) is a chronic inflammatory skin condition characterized by a compromised skin barrier due to a variety of reasons, such as hereditary predisposition, immunological overactivity, and skin microbiome disruption. There is strong evidence linking food allergies (FA) with AD in some children, and many children with AD develop asymptomatic food sensitivity. FA and AD are two frequent childhood illnesses that are closely related. Food allergies affect 30% of kids suffering from moderate and severe eczema and can cause a variety of symptoms, including dry, cracked skin, rash, itchiness, oozing, and crusted skin. While preteens and teens with AD are commonly sensitive to environmental allergens including house dust mites, mold, pollen, or dander of animals, younger kids with AD typically exhibit sensitivity to food items like peanuts, milk, or eggs. A food challenge test (FC) should be used to confirm allergies before recommending a stringent diet that could be hazardous to the patient. While elimination diets continue to be the cornerstone of the management of FA, they should only be carried out under the guidance of a specialist. Topical treatments are crucial for all individuals with AD. Early skin care with emollients, topical steroid treatment, and early introduction of highly allergenic foods are promising methods of alleviating symptoms of AD.

Evaluation of The Safety and Efficacy of Newly Developed Domestic Allergenic Extracts for Skin Prick Testing

Background

Allergic disorders are common health problems worldwide with significant socio-economic impacts. The best diagnostic method using allergenic extract is the skin prick test. Regarding the effects of geo-climatic factors and allergenic extract source material quality, the aim of study was to determine the safety and efficacy of some in-house-developed allergenic extracts.

Methods

Forty-five different allergenic extracts, including common regional pollen, foods, and dog and cat hair, as well as positive and negative extracts, were prepared from domestic sources using optimum extraction methods. All extracts passed stability and sterility testing, and sterile final products containing 50% glycerin in 10 and 20 w/v concentrations were used. Skin prick testing was performed on volunteers and immediate or late side effects were recorded.

Results

In total, 56 students (mean age: 21.2±2.3y, M/F ratio: 1.07) participated in this study. For inhalant allergens, all extracts except dog hair extract caused positive responses. Salsola kali (Russian thistle) and Fraxinus velutina (ash tree) were the most common grass and tree pollen extracts, respectively. Of 18 different food extracts, five, including egg white, tomato, fig, melon, and green pepper caused skin reactivity in only one person. No participant reported any immediate or late side effects, including large local reaction or systemic response.

Conclusion

The result of the current study confirmed the safety of all our in-house-developed allergenic extracts. Regarding efficacy, almost all inhalant and five food allergens caused positive skin responses.

Food Hypersensitivity in Children Aged 0-3 Years of the Lviv Region in Ukraine: A Cross-Sectional Study

Aim: To determine the prevalence and to estimate factors associated with food hypersensitivity in young children of the Lviv region in Ukraine. Methods: A prospective cross-sectional survey study was conducted between 2016 and 2017 in the Lviv region of Ukraine. A specially designed questionnaire about food hypersensitivity of young children developed and validated by M. J. Flokstra-de Blok was used after translation into the Ukrainian language. The questionnaire included 34 questions, grouped into general and detailed information. Parents of children aged 0-3 years were asked to complete the questionnaire at pre-schools and medical institutions. Results: Among 4,500 distributed questionnaires, 3,214 (71%) were completed and processed. Parents reported that 25% of their young children had food hypersensitivity. According to the survey the most common agents involved in food hypersensitivity in young children were cow's milk (34%), egg (28%), and wheat (24%). Hypersensitivity to milk occurred in 50% of children in the age group of 1-2 years. Regional differences associated with food hypersensitivity were also found. Namely, in the Carpathians, there was more hypersensitivity to fish (27%) and honey (22%) than in other regions, while hypersensitivity to soy was detected mostly in Lviv City residents (8.5%). Unknown causes of food hypersensitivity were highly reported (34%) in the Carpathians. Conclusion: Prevalence and some distinctiveness of food hypersensitivity revealed in four geographic and climate zones as well as in Lviv City have a considerable practical use for formulation of recommendations for children with food hypersensitivity.

Are the most common food allergens in an Iranian atopic population compatible with worldwide reports? A systemic review and meta-analysis with molecular classification of frequent allergens

BACKGROUND

Undesirable immunological responses to alimentary allergens are one of the hallmarks of atopic diseases. The prevalence of common food allergens is dissimilar among different communities with distinct nutritional habits and genetic characteristics.

AIM

To assess the prevalence of the most common food allergens in Iran, using different reliable studies.

METHODS

All studies determining sensitization to common food allergens that were indexed in PubMed, Web of Science, Google Scholar, ProQuest, Scopus, Iran Medex, and Magiran were included in this review. To perform a meta-analysis, STATA 14 and metaprop command was applied. A logistic-normal random-effects model with Freeman-Tukey double arcsin transformation was applied to combine the findings of different studies and evaluate their heterogeneity. Random pooled estimate (ES) (pooled prevalence), 95% confidence interval (95% CI) and p-value were determined.

RESULTS

A total of 23 studies with data from a total of 6126 children and adults met the inclusion criteria for entering this meta-analysis. The respective pooled prevalence of a positive family history of allergy and positive specific IgE to at least one food allergen was 72% (95% CI: 66-77%) and 41% (95% CI: 33-49%), respectively. Our results in the total population revealed that allergic sensitization to egg yolk, cow's milk (CM), egg white, and wheat were 25% (95% CI: 16%-35%), 24% (95% CI: 19-29%), 23% (95% CI: 18%-28%), and 9% (95% CI: 6%-14%), respectively. Walnut, peanut, and soybean sensitization was detected in 23% (95% CI: 17%-31%), 23% (95% CI: 13%-33%), and 20% (95% CI: 12%-28%) of patients, respectively. Random pooled ES for sensitization to shrimp and fish was 32% (95% CI: 21-45%) and 12% (95% CI: 6-20%), respectively. The result of analysis in different age groups revealed that allergic sensitization to milk, egg white, and egg yolk declines in higher age groups; while shrimp sensitization increases in older patients. In patients with atopic dermatitis, egg white was the most frequent food allergen 29% (95% CI = 18-42%); while wheat was the least frequent 8% (95% CI = 4-14%).

CONCLUSIONS

Considering the prevalence of different food allergens, the results of the current meta-analysis revealed that egg yolk and cow's milk had the second and third rate after shrimp, respectively. The high prevalence of sensitization to shrimp may be attributed to its high consumption in coastal areas and/or cross-reactivity of shrimp with some aeroallergens such as mites.

Sensitization to common allergens among patients with allergies in major Iranian cities: a systematic review and meta-analysis

Various allergens are implicated in the pathogenesis of allergic diseases in different regions. This study attempted to identify the most common allergens among patients with allergies based on the results of skin prick tests in different parts of Iran. Relevant studies conducted from 2000 to 2016 were identified from the MEDLINE database. Six common groups of allergen types, including animal, cockroach, food, fungus, house dust mite, and pollen were considered. Subgroup analysis was performed to determine the prevalence of each type of allergen. The Egger test was used to assess publication bias. We included 44 studies in this meta-analysis. The overall prevalence of positive skin test results for at least one allergen was estimated to be 59% in patients with allergies in various parts of Iran. The number of patients was 11,646 (56% male and 44% female), with a mean age of 17.46±11.12 years. The most common allergen sources were pollen (47.0%), mites (35.2%), and food (15.3%). The prevalence of sensitization to food and cockroach allergens among children was greater than among adults. Pollen is the most common allergen sensitization in cities of Iran with a warm and dry climate; however, sensitization to house dust mites is predominant in northern and southern coastal areas of Iran.

Epidemiological survey of pediatric food allergy in Mashhad in Northeast Iran

Introduction

Food allergy is an increasing problem worldwide, but the foods responsible for food allergy are not the same in different countries, probably because of the role of genetic, cultural, and nutritional factors. The aim of this study was to determine the common food allergens in pediatric patients with different presentation of food allergy.

Methods

In this cross-sectional study, all of the patients were referred to pediatric allergy clinics affiliated with Mashhad University of Medical Sciences from September 2012 to August 2014. For patients with IgE-mediated food allergy that was diagnosed with clinical manifestations, the skin prick test was done. The results were analyzed by SPSS version 17 and statistical analysis was done with the chi-squared test and the t-test. P values < 0.05 were considered statistically significant.

Results

Three hundred seventy-one patients (53.9% male, 46.1% female) with ages in the range of three months to 18 years were studied. The most frequent food allergen in all patients with decreasing prevalence were egg white (17.8%), pepper (15.8%), curry (14.3%), egg yolk (14%), cow’s milk (10%), and tomato (7.8%). The most common presenting symptoms were respiratory (allergic rhinitis 45%, asthma 32%), dermatologic (atopic dermatitis 30%, urticaria 8.3%), colitis (17.5%), and gasteroesophagial reflux disease (GERD) (2%). According to the prevalence of food allergens in different age groups, we realized that, after the age of three years, the frequency of sensitization to egg white, egg yolk, cow’s milk, wheat and cereals was decreased and allergy to pepper and curry was increased.

Conclusion

The prevalence of culprit foods that produce food allergies depends on several factors, including age, presenting manifestation, and where the patient lives. As many food allergies are outgrown, patients should be reevaluated regularly to determine whether they have lost their reactivity or not.

Common causes of anaphylaxis in children: the first report of anaphylaxis registry in iran

BACKGROUND

: Anaphylaxis is an acute, systemic, and potentially fatal allergic reaction. Many things can cause anaphylaxis potentially but some agents are more common like some foods (milk, egg, soy, wheat, peanut, tree nut, shellfish, and fish), insect stings, medications, latex, and food-dependent exercise-induced anaphylaxis. The goal of this study is to show the common causes of anaphylaxis among the children with anaphylaxis history who were referred to the Immunology, Asthma and Allergy Research Institute (IAARI) during a 4-year period (2005-2009).

METHODS AND MATERIALS

: During those 4 years, we registered all children (<14 years old) with a history of anaphylactic reaction. To prove the cause of anaphylaxis, we performed skin prick tests with suspected agents according to their history and measured specific IgE against them by the ImmunoCAP test. Recognition of common allergens was based on having a positive history for 1 allergen and positive skin prick test or specific IgE for that at the same time, or having positive results from both tests when the allergen was unclear. Idiopathic anaphylaxis was a reaction when any known allergen and positive tests were not obtained.

RESULTS

: One hundred ninety-three nonfatal anaphylactic attacks among 63 children were recognized. In total, the most current cause of anaphylaxis in children was food (89.7%). Milk (49.3%) and wheat (26.1%) were the most common. Other foods were egg (8.7%), nuts (2.8%), and spices (2.8%). Six children (8.7%) were sensitive to multiple food allergens like milk, egg, and wheat. Five (7.1%) of 63 patients had anaphylactic attack because of stinging. Wasp was the trigger in 3 (4.3%) of them and honeybee was the cause in 1 (1.4%). The last one was because of unknown hymenoptera. There were 2 idiopathic cases of all 63 patients.

CONCLUSIONS

: Food allergens, especially milk and wheat, are the most common cause of anaphylaxis in children. Because anaphylaxis can be fatal, it is advisable to recognize its causes in different communities to prevent recurrent attacks.