Background: The effect of specific immunotherapy (SIT) on eczema in atopic dermatitis is not known. Therefore, a multi-centre, randomized dose-response trial, double-blind with respect to the efficacy of a biologically standardized depot house dust mite preparation was performed.
Methods: Eighty-nine adults with a chronic course of atopic dermatitis, SCORAD >or=40 and allergic sensitization to house dust mites [CAP-FEIA >or=3] were included, of whom 51 completed the study. Subcutaneous SIT with a house dust mite preparation (Dermatophagoides pteronyssinus/D. farinae) applying maintenance doses of 20, 2,000 and 20,000 SQ-U in weekly intervals for 1 year. The main outcome measures addressed the change of the SCORAD as average of the values after 9 and 12 months of SIT in comparison with the value at baseline.
Results: The SCORAD declined in the three dose groups in a dose-dependent manner (P = 0.0368, Jonckheere-Terpstra test) and was significantly lower in the two high-dose groups (2,000, 20,000 SQ-U) compared with the low-dose group of 20 SQ-U (P = 0.0379, U-test) after 1 year of SIT. The use of topical corticosteroids was significantly reduced with higher doses (P = 0.0007, Mantel-Haenszel chi-square test).
Conclusions: Allergen-SIT for 1 year with a house dust mite preparation is able to improve the eczema in patients with atopic dermatitis who are sensitized to house dust mite allergens and reduces the need for topical corticosteroids. SIT may be valuable in the treatment of this chronic skin disease.