Allergy tests for food may be falsely positive when they are performed in children who don’t have a history suggesting a serious (IgE mediated) allergy to that food. These results can lead to avoidance of foods to which a true allergy has not been validly documented. When symptoms suggest a food allergy, a careful history should be completed before ordering specific tests, and these should be selected based on the history. A history that suggests serious allergy to a food may include: (1) combinations of the skin, ocular, respiratory, gastrointestinal and cardiovascular symptoms of anaphylaxis that occur within minutes to hours of eating the specific food, or (2) moderate to severe atopic dermatitis. Testing should be selected based on the history and should not include large screening panels.
Sources:
Bird JA, et al. Food allergen panel testing often results in misdiagnosis of food allergy. J Pediatr. 2015 Jan;166(1):97-100. PMID: 25217201.
NIAID-Sponsored Expert Panel, et al. Guidelines for the diagnosis and management of food allergy in the United States: report of the NIAID-sponsored expert panel. J Allergy Clin Immunol. 2010 Dec;126(6 Suppl):S1-58. PMID: 21134576.
Sicherer SH, et al. Allergy testing in childhood: using allergen-specific IgE tests. Pediatrics. 2012 Jan;129(1):193-7. PMID: 22201146.