Oral food challenge test results of patients with food allergy with specific IgE levels >100 UA/ml

Specific IgE level (sIgE) is an important factor indicating sensitization status in children with food allergies (FAs). The present study aimed to clarify oral food challenge test (OFC) results in children with FAs with sIgE levels ≥100 UA/ml compared with those in children with sIgE <100. The retrospective study analyzed patients who underwent OFC with egg white, cow milk and wheat at Gifu Prefectural general medical center, Gifu, Japan between July 2017 and March 2023. Clinical history, total IgE (tIgE), sIgE and correlation between sIgE, sIgE/tIgE and eliciting dose as the amount of intake protein were examined. In the <100 group, positive OFC showed significantly higher sIgE for egg white, ovomucoid and casein than negative OFC (P<0.05); however, there was no significant difference between positive and negative OFC in the ≥100 group. In the <100 group, positive OFC showed significantly higher sIgE/tIgE for ovomucoid, milk and casein than negative OFC (P<0.05); however, there was no significant difference in sIgE/tIgE between positive and negative OFC in the ≥100 group. There was a significant negative correlation between eliciting dose and sIgE for egg white and wheat (P<0.05). For milk and wheat, there was no significant difference between ≥100 group and the <100 group with regard to positive rates in the OFC. Therefore, OFC may be safely performed by decreasing total challenge dose for the ≥100 group.