アレルギー患者の抗原検査法 ＲＡＳＴ・皮内反応の問題点

Abstract

Radioallergosorbent test (RAST), skin test and nasal challenge (provocative) test are used to identify allergen of nasal allergy. We have compared the results of tests to evaluate the methods and to establish appropriate indications for their use.House dust extract is a mixture of numerous allergenic components, mainly mites' component, so there seems to be a close correlation between sensitivities to house dust and mites. One hundred and sixty-two patients were tested with a battery of Dermatophagoides pteronyssinus (D1), Dermatophagoides farinae (D2), house dust by Greer Labos (H1), and house dust by Hollister-Stier Labos. (H2) We found 96% agreement of IgE antibodies to D1 and D2, 92% agreement for D2 and HI and 95% agreement for H1 and H2. We performed provocative tests with house dust by Torii Co. in Japan in 16 skin test-positive but RAST-negative and one skin test-negative but BAST-positive individuals. Twelve of these 17 patients had a nasal response. These results show that house dust in Japan probably contains more components of mites than does that in the United States.In cases of Japanese cedar (Cryptomeria japonica) pollinosis, there is much closer correlation between skin tests and RAST. Thirteen RAST-negative but skin testpositive patients had seasonal symptoms.RAST shows no false positive but sometimes shows false negative results.It therefore follows that RAST should be ordered only after a careful history and physical examination. As a screening test, RAST is too expensive, and excessive use of it should be condemned.