Abstract
A number of opinions have appeared and still under dispute on the etiological factors of bronchial asthma. Detailed inquiries were made by the use of the questionaire card together with clinical observations by the help of various laboratory tests. Results of those studies confirmed the statement of Rackemann that most of the young patients belong to the asthma of external causes while those of the middle age or old belong to the asthma of internal causes. Presence of allergen, however, was suspected even among the patients of the latter group not to speak of the former, and especially the importance of house dust as allergen.
In this connection, with an intention of clarifying the significance of house dust as asthmatic allergen, observations were made on the dermal reactions and the leucolytic phenomenon elicited by the house dust extract as well as on the clinical effect of desensitization treatment.
Positive reactions to the house dust extract were discovered in a high percentage among the asthmatic group with an evident difference from the control group. Leucolytic phenomenon by the house dust extract too was recognized in a larger number of the patients in asthmatic group than the control. The therapeutic effect of desensitization treatment was quite favourable and the presence of the heat stable blocking antibody was demonstrated in the sera of the patients under this treatment (in 5 out of the 13 cases) .
In view of the findings stated above, it is considered that there are a considerable number of the asthmatic patients due to the house dust and that specific desensitization treatment should first be attempted.
