Skin Prick Wheal Size Associated with Allergy Symptom Severity

The size of a skin prick allergy test wheal strongly correlates to patient-reported allergy symptom severity, the results of a study suggest.

The study, which appeared in the March 2014 edition of Clinical & Experimental Allergy, analyzed the results of skin prick tests for 18 inhaled allergens that included those of several grasses, cats, dogs, and several tree species. Of the 3068 participants who received skin prick tests, 2088 showed at least one 3-mm wheal reaction to at least 1 of the allergens.

The prevalence of allergic symptoms increased as skin prick test wheal size increased for 17 of the 18 allergens tested, researchers said. Depending on the allergen, 40% to 89% of positive skin prick reactions resulted in patientreported allergy symptoms. In patients with positive skin prick tests, 80% to 90% had allergic rhinitis. Allergic asthma was present in 30% to 40% of reactions, and atopic dermatitis and food allergies were present in 10% to 20% of reactions.

“The present analyses draw attention to the necessity of skillful interpretation of [skin prick test] results to improve testing quality and to avoid medicalization,” the researchers wrote.