Patch tests - allergy; Scratch tests - allergy; Skin tests - allergy; RAST test
In a nonallergic person, allergy tests should be negative (no response to the allergen).
A positive result means you reacted to a specific substance. Often, but not always, a positive result means the symptoms that you are having are due to exposure to the substance in question. In general, a stronger response means you are more sensitive to the substance.
People can have a positive response with allergy skin testing, but not have any problems with the specific substance in every day life.
The skin tests are generally reliable. However, if the dose of allergen is excessive, a positive reaction will occur even in persons who are not allergic.
Bernstein IL, Li JT, Bernstein DI, Hamilton R, et al. American Academy of Allergy, Asthma and Immunology; American College of Allergy, Asthma and Immunology. Allergy diagnostic testing: an updated practice parameter. Ann Allergy Asthma Immunol. 2008 Mar;100(3 Suppl 3):S1-148.
Demoly P, Bousquet J, Romano A. In vivo methods for the study of allergy. In: Adkinson NF Jr, ed. Middleton’s Allergy: Principles and Practice. 7th ed. Philadelphia, Pa: Mosby Elsevier; 2008:chap 71.
Gober MD, DeCapite TJ, Gaspari AA. Contact dermatitis. In: Adkinson NF Jr, ed. Middleton’s Allergy: Principles and Practice. 7th ed. Philadelphia, Pa: Mosby Elsevier; 2008:chap 63.
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