Diagnostic Decision Points of Specific IgE Concentrations in Korean Children With Egg and Cow's Milk Allergies.
OBJECTIVE
The purpose of this study was to evaluate the utility of specific IgE (sIgE) concentrations for the diagnosis of immediate-type egg and cow's milk (CM) allergies in Korean children and to determine the optimal cutoff levels.


METHODS
In this prospective study, children ≥12 months of age with suspected egg or CM allergy were enrolled. Food allergy was diagnosed by an open oral food challenge (OFC) or through the presence of a convincing history after ingestion of egg or CM. The cutoff levels of sIgE for egg white (EW) and CM were determined by analyzing the receiver operating characteristic curves.


RESULTS
Out of 273 children, 52 (19.0%) were confirmed to have egg allergy. CM allergy was found in 52 (23.1%) of 225 children. The EW-sIgE concentration indicating a positive predictive value (PPV) of >90% was 28.1 kU/L in children <24 months of age and 22.9 kU/L in those ≥24 months of age. For CM-sIgE, the concentration of 31.4 kU/L in children <24 months of age and 10.1 kU/L in those ≥24 months of age indicated a >90% PPV. EW-sIgE levels of 3.45 kU/L presented a negative predictive value (NPV) of 93.6% in children <24 months of age, while 1.80 kU/L in those ≥24 months of age presented a NPV of 99.2%. The CM-sIgE levels of 0.59 kU/L in children <24 months of age and 0.94 kU/L in those ≥24 months of age showed NPVs of 100% and 96.9%.


CONCLUSIONS
Our results indicate that different diagnostic decision points (DDPs) of sIgE levels should be used for the diagnosis of egg or CM allergy in Korean children. The data also suggest that DDPs with high PPV and high NPV are useful for determining whether OFC is required in children with suspected egg or CM allergy.
Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.; Environmental Health Center for Atopic Diseases, Samsung Medical Center, Seoul, Korea.
Jihyun
J
Kim
Department of Pediatrics, Medical Research Institute of Pusan National University Hospital, Pusan National University School of Medicine, Busan, Korea.
Hye Young
HY
Kim
Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.; Environmental Health Center for Atopic Diseases, Samsung Medical Center, Seoul, Korea.
Mi Ran
MR
Park
Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.; Environmental Health Center for Atopic Diseases, Samsung Medical Center, Seoul, Korea.
Jaehee
J
Choi
Environmental Health Center for Atopic Diseases, Samsung Medical Center, Seoul, Korea.
Ji Yeon
JY
Shim
Department of Biostatistics, Samsung Biomedical Research Institute, Seoul, Korea.
Min Ji
MJ
Kim
Environmental Health Center for Atopic Diseases, Samsung Medical Center, Seoul, Korea.
Youngshin
Y
Han
Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.; Environmental Health Center for Atopic Diseases, Samsung Medical Center, Seoul, Korea. kmaped@skku.edu.
Kangmo
K
Ahn
Egg allergy; food allergy; milk allergy; specific IgE