Sensitization to House Dust Mite: Its Associations with Bronchial Hyperresponsiveness and Lung Function in Asthmatic Children

Jin, So Hee; Kim, Eun Ok; Park, Kang Seo

Abstract

PURPOSE:Aeroallergens are generally known to us as risk factors for the persistence of asthma. House dust mites are major aeroallergens in Korea. However, the associations between house dust mites sensitization, bronchial hyperresponsiveness and pulmonary function are still controversial.
METHODS
One hundred eighteen children aged 5-12 years with mild to moderate asthma were enrolled. Each subject underwent the pulmonary function test, the methacholine challenge test, and the skin prick test with aeroallergens, and total serum immunoglobin (Ig)E levels. The non-sensitization group was defined when skin prick test results are all negative for common aeroallergens. The sensitization group was defined when skin test results are positive for Dermatophagoides pteronyssinus or Dermatophagoides farinae.
RESULTS
In the house dust mites sensitization group, increased serum total IgE and decreased methacholine PC(20) were noted. There was no significant difference in pulmonary functions between sensitization and non-sensitization groups. In the sensitization group, methacholine PC(20) correlated with prebronchodilator %FEF(25-75%) (r=0.346, P=0.008) but did not correlate with %FVC, %FEV(1) and FEV(1)/FVC. In the sensitization group, methacholine PC(20) and pulmonary function did not correlate with total IgE or age.
CONCLUSION
The house dust mites sensitization in asthmatic children correlated with increased bronchial responsiveness but did not correlate with decreased pulmonary functions. These findings support the role of house dust mite sensitization in the modulation bronchial responsiveness.