[CLINICAL MANIFESTATIONS AND SAFETY OF AN ORAL FOOD CHALLENGE USING BOILED EGG YOLK].

BACKGROUND: Allergenicity to heated egg yolks is known to be low in hen's egg allergy. However, there are few reports concerning the safety of an oral food challenge (OFC) with boiled egg yolks. This study aimed to determine the safety of a boiled egg yolk OFC and the clinical characteristics of patients who were OFC-positive. METHODS: We retrospectively examined the data of patients who underwent an OFC with one boiled egg yolk at Miyagi Children's Hospital between January 2013 and December 2020. Patients were included if they had a history of immediate symptoms due to hen's egg or positive specific IgE levels to egg yolk or egg white. RESULTS: Among 600 patients, 15.0% were positive for OFC, only one patient required an intramuscular adrenaline injection, and 70% of OFC-positive patients had gastrointestinal symptoms. CONCLUSION: Boiled egg yolk OFC had a low symptom induction rate; however, when symptoms were induced, gastrointestinal symptoms were most commonly observed. Given the low risk of developing severe symptoms, we conclude that the likelihood of safely performing an OFC is high.

Differences in allergic symptoms after the consumption of egg yolk and egg white.

Hen's eggs are one of the most common causes of food allergy. Although hen's eggs are known to cause more gastrointestinal symptoms than other foods, it is not known whether there is a difference in organ-specific symptoms between egg yolk (EY) and egg white (EW). The present study aimed to determine whether there are organ-specific differences in the immediate symptoms of EY and EW in patients with hen's egg allergies. We retrospectively investigated the immediate symptoms and treatment contents of those who had a positive result in an oral food challenge (OFC) of boiled whole EY or 10 g of boiled EW in our hospital from January 2013 to July 2019. We compared 80 patients in the EY-OFC-positive group with 106 patients in the EW-OFC-positive group. The EY-OFC-positive group had significantly fewer respiratory symptoms and significantly more gastrointestinal symptoms than the EW-OFC-positive group and had significantly more gastrointestinal symptoms only. In terms of treatment, significantly fewer patients in the EY-OFC-positive group required beta 2-agonist inhalation, and a significantly higher proportion of patients did not require treatment. Compared to EW, EY is more likely to cause gastrointestinal symptoms and less likely to cause respiratory symptoms. It may be necessary to discriminate between EY and EW allergy during diagnosis.

Use of a home-visit nursing service to manage severe atopic dermatitis in a child with difficult family environment.

Maintenance therapy of atopic dermatitis (AD) with frequent exacerbations needs proactive use of topical corticosteroids or topical calcineurin inhibitors. However, it can be difficult for children in an unfavorable family environment. Home-visit nursing service (HVNS) plays an important role in delivering care to people who need medical help at home. We report a boy in a difficult family situation who received HVNS to successfully manage AD.

Home-based, slow up-dosing oral immunotherapy for hen's egg allergy in an adult patient.

Standard therapy for food allergies involves avoiding causative foods until a patient has outgrown their allergies. Oral immunotherapy (OIT) is an optional treatment for children unlikely to outgrow their food allergy. However, information about OIT in adult patients with food allergies is very limited. We present a case of severe hen's egg allergy (HEA) in an adult who tried home-based, slow up-dosing OIT, reported to have been tolerable and effective in children. A 20-year-old woman with HEA experienced repeated anaphylaxis since childhood when she consumed a small quantity of hen's egg, so she completely avoided hen's eggs. She underwent inpatient oral food challenge (OFC) with 10-g boiled egg yolk and presented lip swelling and abdominal pain. OFC with 1-g boiled egg yolk the following day induced no adverse reaction. OIT was initiated using a home-based, slow up-dosing protocol. She consumed 1 g of boiled egg yolk at home every day, increasing this by 5%-10% every 2 weeks. She started 0.5-g boiled egg white after reaching a whole egg yolk. If adverse reactions occurred, the daily dose was decreased. After 59 months, she was able to eat an entire boiled egg. Anaphylaxis occurred 3 times during OIT due to accidental consumptions of egg products or insufficient heating of egg. Home-based, slow up-dosing OIT might be applicable for adults with severe HEA. It should be performed with appropriate equipment and education for patients, in case of emergency.