Management of IgE-mediated food allergy in the 21st century

Dietary Intervention during Weaning and Development of Food Allergy: What Is the State of the Art?

Food allergy (FA) affects approximately 6-8% of children worldwide causing a significant impact on the quality of life of children and their families. In past years, the possible role of weaning in the development of FA has been studied. According to recent studies, this is still controversial and influenced by several factors, such as the type of food, the age at food introduction and family history. In this narrative review, we aimed to collect the most recent evidence about weaning and its role in FA development, organizing the gathered data based on both the type of study and the food. As shown in most of the studies included in this review, early food introduction did not show a potential protective role against FA development, and we conclude that further evidence is needed from future clinical trials.

Variation in the Allergenicity of Scrambled, Boiled, Short-Baked and Long-Baked Egg White Proteins

BACKGROUND

Hen's egg white (HEW) is the most common cause of food allergy in children which induces mild to fatal reactions. The consultation for a proper restriction is important in HEW allergy. We aimed to identify the changes in HEW allergenicity using diverse cooking methods commonly used in Korean dishes.

METHODS

Crude extract of raw and 4 types of cooked HEW extracts were produced and used for sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE), enzyme-linked immunosorbent assay (ELISA), and ELISA inhibition assays using 45 serum samples from HEW allergic and tolerant children. Extracts were prepared; scrambled without oil for 20-30 seconds in frying pan without oil, boiled at 100°C for 15 minutes, short-baked at 180°C for 20 minutes, and long-baked at 45°C for 12 hours with a gradual increase in temperature up to 110°C for additional 12 hours, respectively.

RESULTS

In SDS-PAGE, the intensity of bands of 50-54 kDa decreased by boiling and baking. All bands almost disappeared in long-baked eggs. The intensity of the ovalbumin (OVA) immunoglobulin E (IgE) bands did not change after scrambling; however, an evident decrease was observed in boiled egg white (EW). In contrast, ovomucoid (OM) IgE bands were darker and wider after scrambling and boiling. The IgE binding reactivity to all EW allergens were weakened in short-baked EW and considerably diminished in long-baked EW. In individual ELISA analysis using OVA+OM+ serum samples, the median of specific IgE optical density values was 0.435 in raw EW, 0.476 in scrambled EW, and 0.487 in boiled EW. Conversely, it was significantly decreased in short-baked (0.406) and long-baked EW (0.012). Significant inhibition was observed by four inhibitors such as raw, scrambled, boiled and short-baked HEW, but there was no significant inhibition by long-baked HEW (IC50 > 100 mg/mL).

CONCLUSION

We identified minimally reduced allergenicity in scrambled EW and extensively decreased allergenicity in long-baked EW comparing to boiled and short-baked EW as well as raw EW. By applying the results of this study, we would be able to provide safer dietary guidence with higher quality to egg allergic children.

Current and Future Treatment of Food Allergies

Food allergy prevalence is rapidly growing among school-age children in the United States, posing a significant health concern in school settings. This article aims to provide an overview of the current state of food allergy treatment options, emergency food allergy care plans, and using epinephrine autoinjectors. In addition, it explores potential future treatment options, including immunotherapy and novel therapeutic approaches. This article emphasizes the crucial role of school nurses in recognizing the treatment options currently available to students and their families, as well as fostering a safe environment for students with food allergies.

Methodological Principles of Nasal Food Challenge

Thanks to their valuable assessment possibilities (subjective complaints and changes in nasal patency during the examination), nasal provocation tests may serve as an alternative tool for oral food challenges in the future. However, this test requires successive attempts to regulate its methodology in order to develop a standardized lyophilisate form and determine the threshold dose for a positive result. The study objective was to present the methodological foundation for nasal food allergen provocation tests induced by freeze-dried powdered chicken egg whites. A control group of 25 individuals with no history of allergy to chicken eggs or any other allergy was included in the study. Optical rhinometry and visual analog scales were used to assess the response of nasal mucosa to local allergen challenges. Minor variations in nasal flows, as measured by optical rhinometry, were observed in the provocation tests. The mean optical density measurements (as measured regardless of the allergen dose used) varied from positive to negative values and vice versa, e.g., amounting to 0.018 OD (standard deviation 0.095) at 15 min and -0.011 OD (standard deviation 0.090) at 30 min. No significant differences were observed concerning the perceived nasal discomfort using the visual analog scale. Due to the absence of nasal mucosal reactivity, nasal challenge is an excellent methodological tool for implementing food allergen tests.

Pearls and Pitfalls of Weaning an Infant with Severe Atopic Dermatitis and Sensitization/Allergy to Food

Atopic dermatitis (AD) is a common chronic inflammatory skin disorder in childhood. Skin barrier impairment exposes infants to food allergens, potentially causing sensitization followed by IgE-mediated food allergy. We describe the case of an infant with severe AD in whom several sensitizations to foods are detected, with consequently difficult weaning, and a history of anaphylaxis to cashew nut. Foods for which skin tests were negative were introduced into the infant's diet. Then, when AD control was managed, oral food challenges (OFCs) for foods to which the patient was sensitized, with the exception of cashew nut, were performed. The simultaneous presence of sensitization toward multiple foods made it difficult to introduce them using classic OFC. Therefore, it was decided to perform the low-dose, gradual controlled OFC. This led to an introduction of sensitized foods into the infant's diet, with the exception of cashew nut, avoiding allergic reactions. Absolute recommendations on how, when, and where to perform OFCs with allergenic food to which the child with AD is sensitized are lacking so far. In our opinion, OFCs and the subsequent ntroduction of allergenic foods should be individualized, evaluating some factors such as their social and nutritional importance, the patient's age and clinical phenotype (including the history of anaphylaxis), and the sensitization profile. There is agreement on the fact that the dietary approach in children with moderate-severe AD should no longer include a strict elimination diet. We believe that an early, gradual controlled introduction of all allergenics to identify the amount of food tolerated in the absence of reactions, even if low dose, may improve patients' and families' quality of life. However, even if discussing a vast relevant literature, the limitation of our work is that we describe the management of a single patient. Extensive and high-quality research is needed in this field to improve the available evidence in the area.

Hidden and Rare Food Allergens in Pediatric Age

In food allergy management, the avoidance of the allergen that caused the reaction plays a fundamental role. Nevertheless, that can be thwarted in case of accidental exposure to a rare or hidden allergen, causing the adoption of a monotonous diet and a consequent reduction in the quality of life of the patient and their family. The identification of a rare and hidden allergen is an important diagnostic challenge, taking into account that a significant proportion of all food reactions is in reality due to them. The aim of the present review is to provide the pediatric allergist an overview of the possible sources of rare and hidden food allergens, taking into consideration the routes of exposure to these potential allergens with the main examples published in the scientific literature and the distinction between types of direct or cross-contamination. The identification of the allergen responsible for the reaction and the provision of a dietary advice customized for the specific individual’s dietary habits is essential to improve quality of life of the familiar nucleus and to reduce the risk of further allergic reactions.