A PROSPECTIVE STUDY ON HYPOSENSITIZATION WITH DERMATO-PHAGOIDES PTERONYSSINUS (D.PT.) EXTRACTS PREPARED FROM WHOLE MITE CULTURE AND MITE BODIES

Abstract

Immunotherapy with inhalant allergen extracts in allergic asthma is still under debate. In order to study its immunological efficacy, 24 asthmatic children sensitive to D.pt. (skin test, specific serum IgE, bronchial provocation test) were given immunotherapy using partially purified and standardized extracts from the whole mite culture (WMC, N=12) or mite bodies (MB, N=12) in a double blind way. Both extracts were characterized by their allergen content and concentrations of the major allergens DP 42 and DP X. The allergen dose during immunotherapy was increased up to each patient's maximum tolerated dose. Before therapy as well as after 6 and 12 months all patients were evaluated by skin titration, bronchial provocation tests, histamine release from washed leukocytes and specific serum IgE and IgG antibodies. Allergen specific bronchial sensitivity was expressed as the allergen concentration necessary for a decrease in FEV1 of 20% (PD20), leukocyte sensitivity as the allergen concentration necessary for 30% histamine release (HR30). The results showed a significant decrease of bronchial sensitivity (p < 0.01) and leukocyte sensitivity (p < 0.01) to D.pt. after 6 and 12 months as well as an increase of specific serum IgG in both, the WMC and the MB group. Skin reactivity to D.pt. tended to decrease in both groups. We conclude from our data, that after 1 year of immunotherapy extracts from both, WMC and MB are effective in inducing immunologic changes and decreasing bronchial sensitivity in D.pt. allergic asthmatic children.