Allergy testing

Percutaneous and intradermal skin tests and laboratory assays of specific IgE antibodies may be useful in selected cases of allergy management. Percutaneous testing kits are available from various manufacturers. A number of common allergens are available in standardized preparations. Positive and negative skin controls are important in establishing reliable results. Antihistamine medications can interfere with skin testing and should be stopped beforehand. Serious reactions to skin testing are rare. Establishing the sensitivity and specificity of percutaneous testing is difficult because there is no widely accepted gold standard for defining a true allergic reaction. Intradermal testing is more sensitive than percutaneous methods but much less specific. Its use is restricted to testing for allergy to insect stings or penicillin. In cases where skin testing is not available or desirable, laboratory assays for IgE antibodies to specific allergens may be used. These assays are generally less sensitive than skin testing methods. Selected patients with allergic rhinitis or asthma that is not controlled with standard therapy may benefit from allergy testing, especially when it can target allergen avoidance measures or guide immunotherapy.