Abstract
In patients of nasal allergy, the positive intracutaneous reactions ot several kinds of allergen extracts are often observed. For example, the positive reactions to ragweed pollen extract were obtained in the same percentage as those to the extract of Japanese cedar pollen. It seems strange that the positive reactions are obtained inspite of no ragweed colony in the district of Nikko. Therefore the authors consider that there is some problem on the present standard of the examination. From the results of examination on patients of nasal allergy in Tokyo and Japanese cedar pollinosis in Nikko, it seemed reasonable that the diagnostic borderline of intracutaneous reactions of ragweed pollinosis be set around 50 mm in erythema and 14 mm in wheal. While, in order to solve this problem using the present standard of the examination, the soulution of allergen extracts with high sensitizing power as ragweed pollen must be diluted. In conclusion, the authors propose that the dilution of allergen extract must be 1:500,000 or 1:1,000,000 in ragweed pollen.
