Correlation of cat-hair (Fel d1) prick skin test to airway response using a live-cat-room challenge model

The purpose of this study was to document the relationship between prick skin test, airway, and common allergy symptom responses to natural cat exposure. Twenty-nine volunteers with a history of cat-hair allergy and asthma were recruited. Subjects had spirometry and prick skin test with Fel d1 on Visit 1. On Visit 2, subjects had a live-cat-room challenge with airway responses and allergy symptoms monitored. All 29 subjects had a positive skin test (wheal > or = 4 mm), but only 12 (41%) had a positive airway response (fall in FEV1 > or = 15%). There was no significant correlation between the fall in FEV1 and wheal size. All symptom scores increased significantly from baseline, but the change was not significantly related to wheal size. In summary, prick skin test response is not a good predictor of airway response or changes in allergy symptoms using the live-cat-room challenge model.