TDNet Discover

Background: Food allergies have been associated with around one-third of children diagnosed with moderate to severe atopic dermatitis. Currently, diagnosing a food allergen is best done through the double-blind placebo-controlled oral challenge. However, some limitations exist in this form of testing including cost, application and interpretation difficulty, and risk of anaphylaxis. Other methods are available, such as the atopy patch test (APT) and the skin prick test (SPT). However, their efficacy is debated among the medical community. Objective: To determine if the atopy patch test is as efficacious as food challenge in diagnosing food allergies in children with atopic dermatitis. Methods: This evidence based medicine systematic literature review accessed databases from October 5, 2018 to June 31, 2019, and consisted of PubMed, Discover, and Google Scholar. The search phrases used in each database were “Atopy patch AND food allergies,” “Atopy patch AND food allergy,” and “Atopy patch AND dermatitis.” Inclusion criteria consisted of food allergies with atopic dermatitis, diagnosis of food allergies through atopy patch, and diagnosis of food allergies specifically in children. Limitations of the studies include articles published within the last 10 years, human subjects, English language, full text articles, meta-analyses, systematic review, peer-reviewed, and randomized control trial. Results: Three studies with the highest forms of evidence available in the literature to answer the proposed research question were chosen after being reviewed. The studies included two systematic reviews and meta-analyses and one prospective self-controlled cohort. In the first systematic review and meta-analysis by Luo et al. (2019), the results indicate strong evidence for the specificity of APT but suggest it lacks sensitivity. Results from the second systematic review and meta-analysis by Soares-Weiser et al. (2014), suggest APT has good specificity but poor sensitivity. In the prospective self-controlled study by Visitsunthorn, Chatapornvorarux, Pacharn, iv. SCREENING ALLERGIES IN ATOPIC DERMATITIS & Jirapongsananuruk (2016), findings suggest that APT is highly specific but has poor sensitivity. Conclusions: Combined evidence for the present research study indicates APT has great specificity but poor sensitivity. APT has proven useful in the diagnostic process and is most appropriate in patients with a high suspicion for food allergies. Only one high level of evidence was specific to discussing diagnosis of a food allergy in children with atopic dermatitis. Further research needs to be done to assess accurately the APT’s efficacy in this specific population. Additionally, future studies on the accuracy of APT should focus on greater sample sizes, specific cutoffs, and better representation of the general population.