OBJECTIVETo study the atopy spectrum and the influence of clinical characteristics upon it in asthmatic children under 4 years of age.

METHODSClinical data of 62 asthmatic children under 4 years of age, including age, sex, the age of first wheezing attack, the total times of wheezing attack, the duration of history of wheezing, and the allergic history of both children and parents, were collected. The screening tests on allergens (fx5E, mx2 and Phadiatop) were conducted by fluoroenzyme-immunometric assay using the UniCAP100 system. The total serum IgE level was also measured. Logistic regression was used to analyze the effect of clinical characteristics on allergic sensitization.

RESULTSThe positive rates of fx5E, mx2 and Phadiatop were 40.3%, 14.5% and 14.5% respectively, and the total allergic sensitization screening test rate was 46.8%. The sensitization rate to inhalant allergens was 24.2%. The allergic history of parent (s), the sensitization to food allergens, the age of first wheezing attack and total serum IgE level were main factors influencing the sensitization to inhalant allergens.

CONCLUSIONSAbout a quarter of asthmatic children under 4 years of age showed sensitization to inhalant allergens. The asthmatic history of parent (s), the sensitization to food allergens, the age of first wheezing attack greater than 2 years and the significantly higher total serum IgE level may increase the possibility of sensitization to inhalant allergens in asthmatic children under 4 years of age.