From the Guidelines
Proactive allergy testing in children without specific symptoms is generally not recommended. This approach is supported by the most recent and highest quality study, which highlights the poor predictive value of widespread screening tests, such as skin prick tests (SPTs) and serum food-specific IgE (sIgE) blood tests, in the absence of clinical context 1. Routine screening can lead to false positive results, causing unnecessary anxiety and dietary restrictions that may negatively impact a child's nutrition and quality of life.
Some key points to consider include:
- The rate of self-reported food allergy among children is often inflated, with one meta-analysis showing a rate of 12% compared to 3% when confirmatory testing was performed 1.
- Positive test results by SPT or sIgE blood tests do not necessarily confirm an allergy, as these tests detect IgE antibodies to the food but are not intrinsically diagnostic 1.
- Overdiagnosis and misinterpretation of results can lead to inappropriate interventions, including unnecessary elimination diets that may increase the risk of developing true food allergies rather than preventing them 1.
- Targeted allergy testing should only be performed when there are specific symptoms suggesting an allergic reaction, such as hives, swelling, breathing difficulties, or persistent gastrointestinal symptoms after exposure to potential allergens.
The risk-to-benefit ratio of allergy evaluation should be considered on an individual basis, especially for highly allergenic foods in high-risk young children 1. A symptom-based approach ensures that testing is clinically relevant and that results can be properly interpreted within the context of the child's medical history and presentation. This approach is supported by the guidelines for the diagnosis and management of food allergy in the United States, which conclude that insufficient evidence exists to recommend routine food allergy testing prior to the introduction of highly allergenic foods in children who are at high risk of reacting to the introduction of such foods 1.
From the Research
Allergy Testing in Children
- Proactive allergy testing in kids is not recommended due to several reasons, including the potential for false positives and the lack of correlation between test results and clinical symptoms 2, 3.
- Allergy testing should only be performed in children with persisting or recurrent symptoms suggestive of an allergy, as it can help identify the allergic trigger and guide treatment 4, 5.
- Skin testing, including prick and intradermal testing, is a common method used to diagnose allergies, but it should be interpreted in the context of clinical symptoms and medical history 2, 6.
- The diagnosis of allergy can only be made by correlating skin testing results with the presence of clinical symptoms, as many patients may have positive skin test reactions without corresponding symptoms 2.
Limitations of Proactive Allergy Testing
- Proactive allergy testing may lead to unnecessary avoidance measures and anxiety for families, especially if the test results are not correlated with clinical symptoms 2, 3.
- There is limited evidence to support the use of proactive allergy testing in asymptomatic children, and it may not be cost-effective or practical 4, 5.
- Allergy testing should be tailored to the individual child's symptoms and medical history, rather than being performed proactively on all children 4, 6.