PURPOSE OF THE STUDY.
To determine the frequency and circumstances of allergic reactions to common food allergens in a multicenter, prospective study of preschool-aged children.
The cohort examined was already participating in an observational study to monitor for development of peanut allergy in patients with history of milk/egg allergy. There were 512 infants enrolled between the ages of 3 and 15 months from 5 US sites.
In a prospective, 5-site observational study, subjects were scheduled for a clinical evaluation at 6-month intervals for 2 visits, then yearly with telephone contacts between each visit. Baseline immunoglobulin E to specific allergen was also obtained. Written and verbal specific food allergen avoidance instructions, along with treatment plans with prescriptions for self-injectable epinephrine were provided. A 36-item questionnaire obtained details about the occurrence of an immunoglobulin E–mediated reaction, including symptoms and time of occurrence, trigger, route of exposure (accidental versus purposeful), and response to reaction.
Over the median follow-up of 36 months, annualized reaction rate was 0.81 per year for all foods (367/512 subjects reporting 1171 reactions) with 56% reporting >1 reaction. Most were triggered by milk (42.0%), egg (21.0%), and peanut (7.9%). Most (64.9%) accidental allergic reactions were attributed to lack of vigilance (eg, label-checking errors and unintentional ingestion). Additional errors included cross-contact in meal preparation and food not provided by actual caregivers. Approximately 11% of reactions were attributed to nonaccidental exposure. Of the 11.4% of reactions that were severe, only 29.0% of them were treated with epinephrine because the caregiver did not recognize the severity, the epinephrine was unavailable, or the caregiver was afraid to administer it.
Because of the high frequency of reactions in preschool-aged subjects, there needs to be an emphasis on improving education in the parent and other caregivers about exposure prevention and anticipatory guidance. The education needs to include indications for epinephrine use and proper technique, as well as potential complications.
This novel prospective, observational study used a large cohort of preschool-aged children. The number of purposeful exposures and the lack of vigilance, despite initial anticipatory guidance, is remarkable. This article emphasizes the importance of providing patients and all caregivers with anticipatory guidance at every clinic visit and reviewing their knowledge of the potential reaction on exposure. It is very important to emphasize the need for supervision, label reading, possible dangers of unsupervised allergen reintroduction, and the symptoms that warrant treatment with epinephrine. The study is limited by parental bias in reporting reaction and circumstances, as well as recall bias.
- Copyright © 2013 by the American Academy of Pediatrics