Comparison of the efficacy and safety of pollen allergen extracts using skin prick testing and serum specific IgE as references

Abstract

© 2017, Allergy and Immunology Society of Thailand. All rights reserved. Background: Allergen extracts may be different due to the difference in dissemination of allergen-containing species in various geographical areas. Therefore, we wish to develop our own extracts to ensure the precision and quality of diagnosis. Objectives: To compare the efficacy and safety of our locally prepared pollen allergen extracts to imported ones, using skin prick testing (SPT) and serum specific IgE (sIgE) as references. Methods: This prospective, randomized, double-blinded, self-controlled study was performed in respiratory allergic adult volunteers who are sensitized to at least one kind of pollen. Each subject was pricked with our Bermuda grass, Johnson grass and careless weed pollen allergen extracts, and also with the imported ones. sIgE levels were measured by using ImmunoCAP®. Results: In 68 volunteers, our Bermuda, Johnson and careless weed extracts showed 91.2%, 45.6% and 54.4% positive SPTs, respectively, while for the imported ones 73.5%, 45.6% and 54.4% SPTs were positive, respectively. No adverse reaction was found in all procedures. The concentration of 10,000 BAU/mL of Bermuda grass, 1: 20 w/v or 10,000 PNU/mL of Johnson grass and 1: 40 w/v or 10,000 PNU/mL of careless weed yielded the most positive SPT results. There was no significant difference in mean wheal diameter (MWD) yielded from using local and imported extracts. Significant correlation was found between MWDs of imported pollen extracts and serum sIgE levels (p < 0.01). Conclusion: No significant difference between SPT results of local and imported pollen allergen extracts was found. Significant correlation was found between MWDs of imported pollen extract SPT and serum sIgE levels.