Methods : Korean children aged over 12 months with suspected IgE-mediated peanut allergy were enrolled. The diagnosis for peanut allergy was confirmed by an open OFC or through the presence of anaphylaxis history. The cutoff levels of sIgE for peanut and peanut components were determined by analyzing the receiver operating characteristic curves.
Results : Forty-eight children (22 boys and 26 girls) with suspected peanut allergy were analyzed. The previously established DDP for peanut-sIgE antibodies ( >14 kU/L) showed the sensitivity of 22.7%, specificity of 100%, PPV of 100%, and NPV of 60.4% in our study population. The median levels of peanut-sIgE (5.44 kU/L vs. 1.14 kU/L, P<0.0001) and Ara h 2–sIgE (0.8 kU/L vs. 0.0 kU/L, P<0.0001) were statistically significant higher in the peanut-allergic group than in the peanut-tolerant group. The peanut-sIgE concentration indicating a positive predictive value (PPV) of 100% was 10.3 kU/L. The Ara h 2-sIgE level of 4.03 kU/L showed PPV of 100%.
Conclusion : Our result showed that the previously established DDP of peanut-sIgE level may be useful predictor for the outcomes of OFC in Korean children suspected of peanut allergy and Ara h 2 is the most important allergen in Korean children with peanut allergy. The cutoff levels for peanut (10.3 kU/L) and Ara h 2 (4.03 kU/L) might be helpful for the diagnosis of peanut allergy in Korean children.