A study on late allergic reactions to house dust mite in bronchial asthmatics.

Patterns of skin and bronchial reactions to the allergen were examined in thirty perennial asthmatics who showed a positive early cutaneous reaction (ECR) to the skin prick test with Dermatophagoides farinael. A dualcutaneous reaction (DCR) was elicited in nine subjects by the skin prick test and in twenty-four by the intradermal test. The size of the late cutaneous reaction (LCR) to the intradermal test was found to correlate with that of the preceding ECR. A bronchial provocation test resulted in no reaction in six, and isloated early asthmatic reaction (EAR) in three, and a dual asthmatic reaction (DAR) in twenty-one. A large LCR was associated with the occurrence of DAR and the patients with a large LCR required a lower allergen concentration to elicit an EAR.