Serum IgE Standardized for Age in Korean Children and Its Diagnostic Reliability in Childhood Asthma

ABSTRACT

PURPOSE: IgE was identified by Ishizaka as an antibody that is reacted at Type I hypersensitivity reaction, and has been used in the diagnosis of allergic disease and the differential diagnosis of extrinsic and intrinsic asthma. But there was some confusing in the diagnosis because of the broad range of measured serum IgE. Recently it was reported that serum IgE should be standardized for area and age to give the diagnostic reliability. METHODS: We measured serum IgE in 512 Korean children admitted at Ewha Woman University Mokdong Hospital between March 1991 and March 1994 and studied the relationship between asthma and serum IgE standardized for age in Korean children. RESULTS: 1) The geometric mean of serum IgE in non - allergic children and asthma were increased gradually according to age. The ranges of measured IgE in each group were overlapped in some part. 2) Log IgE increased by age similarly in asthma and non - allergic children, but was higher in asthma children than non - allergic children. Z scores of log IgE in asthma children increased by age, but those in non - allergic children was not changed by age. 3) Log IgE in male was not significantly different to that of female (p>0.05). 4) Incidence of asthma increased by increasing of Z score of log IgE standardized for age(p<0.05). 5) The normal range of serum IgE standardized for age was presented. Asthma was absent in children below the lowest normal IgE level (log IgE-1.5SD). CONCLUSIONS: Serum IgE if standardized by age, would be much valuable for the diagnosis of asthma in children.