Although children, with allergic airway disease, who are sensitized to house-dust mite (HDM) are known to have increased levels of
allergen-specific
IgE and
IgG, the association between the quantity of those
immunoglobulins and the clinical features of disease is not yet well established. The purpose of this study was (i) to evaluate Der p1-specific
IgA,
IgG1,
IgG4, and
IgE levels of children with HDM-allergic
asthma and
allergic rhinitis and to compare it with that of healthy controls (ii) to assess the association with disease duration. A total of 73 patients were included. Of those, 58 had
asthma (M/F: 27/31, mean age 7.9 +/- 2.7 yr) and 15 were diagnosed as
allergic rhinitis (M/F: 8/7, mean age 10.1 +/- 4.0 yr) without
asthma. Twenty-five (M/F: 13/12, mean age 9.5 +/- 4.2 yr) non-allergic children were included as healthy controls. Data on age at onset and duration of disease were recorded. Then, Der p1-specific
IgA,
IgG1,
IgG4,
IgE levels were measured in all of the 98 subjects by ELISA. Comparison of Der p1-specific antibody levels of patients and controls revealed that Der p1-specific
IgG1,
IgG4 and
IgE levels of patients with
asthma (p = 0.012, p = 0.021, p = 0.004, respectively) were significantly higher than healthy controls. Also, the ratio of Der p1-specific
IgA/
IgE was significantly lower in asthmatic children when compared with children with
allergic rhinitis and controls (p = 0.029, p < 0.001, respectively). Der p1-specific
IgG1,
IgG4,
IgE and
IgA levels of asthmatic children with duration of disease of >or=4 yr were significantly higher than those with disease duration of <4 yr.
IgA/
IgE ratio was not significantly different in those two groups of asthmatics. We concluded that although all of the specific antibody levels increased with longer duration of
asthma,
IgA/
IgE ratio remains to be low in asthmatic children allergic to HDM.