Home-based oral immunotherapy (OIT) with an intermittent loading protocol in children unlikely to outgrow egg allergy.

Background: Home based oral immunotherapy (OIT) for food allergy has often been used for young children in Japan, the majority of whom are believed to outgrow the allergy by the school age, therefore the true efficacy of the therapy has been controversial. The aim of this study was to evaluate the efficacy and safety of a newly developed slow- type home-based oral immunotherapy (OIT) regimen in children with hen's egg (HE) allergy, who had low likelihood of outgrowing the allergy, with treatment involving only elimination diet.

Method: We retrospectively reviewed the medical records of 43 children with egg allergy (30 males; median age 6) who fulfilled Burks et al.'s criteria of being unlikely to outgrow the allergy. Thirty children who agreed to start OIT were assigned to the treatment group, and 13 who did not want to participate immediately were assigned to the untreated group; the patients underwent an elimination diet for 1 year, during which they were monitored. The OIT regimen involved the intake of the maximum tolerated dose 2 to 3 times a week at home, with initial dose introduction followed by dose build-ups with medical supervision. We statistically evaluated the rate of children who changed their threshold up to 32 g of egg - defined as, oral tolerance induction- in both the groups for 1 year and in the OIT group for 2 years, as well as the rate of children who fulfilled Savage et al.'s criteria of clinical tolerance after reaching the abovementioned remission stage.

Results: The rate of children who achieved oral tolerance induction to 32 g of egg after 1 year in the OIT group (9/30) was significantly higher than that in the untreated group (0/13). The total rate within the OIT group was significantly increased from 9/30 at 1 year to 17/30 at two years without any severe adverse reaction; of the above 17 children, we followed 14 children, and noted that 11 of these were able to obtain clinical tolerance.

Conclusion: The home-based OIT with an intermittent loading protocol was very safe and effective in children with a low likelihood of outgrowing egg allergy.