The Usefulness of an Phadiatop(R)Infant as a Allergic Screening Test in Korean Children

Kim, Byoung Ju; Lee, Jung Yong; Song, Young Hwa; Yu, Jinho; Oh, Heung Bum; Hong, Soo Jong

Abstract

PURPOSE
Atopy is a prerequisite for IgE-mediated allergic disease and also a significant prognostic factor. Phadiatop(R)Infant (phadia AB, uppsala, sweden) is a new blood test designed for the detecting the presence of IgE sensitization in young children. This study aims to investigate the usefulness of Phadiatop(R)Infant test in Korea.
METHODS
Among the patients who visited Childhood Asthma Atopy Center, Asan Medical Center between January 2008 and August 2008, young children under 6 years of age who had eczema or wheezing were enrolled. Ninety-three patients were tested using specific IgE antibody tests with 6 aeroallergen including Dermatophagoides pteronyssinus (D.p), Dermatophagoides farinae (D.f), cat, dog, cockroach and alternaria, and 6 food allergen including egg, milk, soybean, wheat, fish and peanut as well as Phadiatop(R)Infant test.
RESULTS
The study group was consisted of 54 males and 39 females, with a mean age of 32.4+/-20.4 months. By specific IgE antibody test, 38.7% were sensitized to aeroallergen, 53.8% to food allergen, 71% to at least one allergen. Positive rate of Phadiatop(R)Infant was 66.9%. There were 9 discrepant cases: 4 cases with positive Phadiatop(R)Infant but negative specific IgE antibody test and 5 cases with negative Phadiatop(R)Infant but positive specific IgE antibody test. The former cases except one were older than 36 months and all the latter cases were sensitized to house dust mite. The kappa value between Phadiatop(R)Infant and specific IgE antibody test was 0.768. When the age was considered, the younger children showed the better agreement rate [kappa value=0.933 (<24 months), 0.692 (24-48 months) and 0.619 (>48 months)].
CONCLUSION
Phadiatop(R)Infant may be a useful screening test for atopy in Korean children, especially in younger children. It is presumed that the rates of sensitization to local inhalant allergen become higher with increasing age.