Clinical experience of provocation tests by SQ injection of allergen immunotherapy extracts

Lee, Ki Young

Abstract

BACKGROUND AND OBJECTIVES: Allergy skin prick test is an essential step before deciding allergen immunotherapy. In this study, we evaluated the clinical significance of allergy skin prick test to confirm causative allergen in prescribing allergen immunotherapy. METHOD: Single vaccines prepared for immunotherapy were injected by subcutaneous route in 50 asthmatic children showing positive responses on allergy skin prick test. A total of 87 allergens were used in this study. Single vaccines were diluted and injected from 1:10,000 dilution and increased up to stock solution. If asthmatic symptoms occurred, the tests were stopped and considered as positive reactions. If no reaction to 0.5ml of stock solution occurred, the result was considered to be a negative reaction.
RESULTS
Asthmatic symptoms occurred in 43.7% of all tested cases within 30 minutes. Of them, Alternaria was the most commonly provoked antigen(72.7%) followed by house dust (46.7%) and D. farinae(45.5%). The end-point of allergens needed for provocation of asthmatic symptoms included stock solutions in 65.8% of cases and X10, X100 and X1,000 dilutions in 18.4%, 5.3% and 10.5% respectively. Immunotherapy was administered in 31 cases for those provoked by injection of vaccines for conventional immunotherapy. 54.8% tolerated upto the `endpoint' concentration of allergens without any symptoms.
CONCLUSION
Allergy skin prick test is closely related with etiologic allergens based on provocation test results in more than half of the study subjects.