Study design
This study was conducted as a part of prospective cohort study for food
allergic children (UMIN000013561). Concurrent with routine medical
examinations at Sagamihara National Hospital, data on AAR were collected
from outpatients at intervals of 2–4 months between January and
December 2020. The study included children aged 0–18 years with a
pediatrician-provided diagnosis of an immediate-type food allergy based
on the following criteria: developing an allergic reaction in an OFC or
having a history of allergic symptoms to HE, CM, wheat, or peanuts
within 2 years before study initiation. Children diagnosed with a
non-IgE-mediated food allergy or food-dependent exercise-induced
anaphylaxis, who had received oral immunotherapy (OIT), whose slgE
levels had not been evaluated, or whose threshold dose had not been
obtained within 2 years before the initiation of the study were
excluded. Baseline data of the participants were collected at the
beginning of the study. The allergic reactions were defined based on
Japanese guidelines for food allergies.4
During regular follow-up visits over 2–4 months, pediatricians asked
outpatients or their parents/guardians whether the patient had
experienced AAR between the last visit and the current visit. For
children who had experienced AAR, additional questions were asked
regarding the dietary form, severity of symptoms, organ symptoms,
treatments required, causative food, site, and cause of ingestion.