Comparison of the Results of Open Oral Food Challenge Test in Allergic Children with Positive ‎Skin Prick Test to Cow's Milk, Egg and Wheat

Considering the need to perform a food challenge test in suspected food allergy cases, the purpose of this study was to investigate the results of the open oral food challenge (OFC) test in children with allergies and compare its results with their skin prick test (SPT).

In this descriptive, cross-sectional, retrospective study, we reviewed the records of 63 allergic children with a positive SPT to cow milk, egg, or wheat, who had referred to the allergy and immunology subspecialty clinic in Kashan, Iran. The patients with positive SPT for the studied allergens, received complete allergen restriction diet for 3 months. After 3 months, open OFC test was performed according to the protocol. Data were analyzed using descriptive statistics and inferential statistics (Chi-square test to investigate the relationship between the response type in OFC and qualitative variables).

The mean age of the children was 6.46±3.14 years and more than half of them were girls. Most children were allergic to cow milk (54%). 25.4% of allergic children responded negatively to the open OFC test. 26.5%, 29.4%, and 16.7% of the children who were allergic to cow milk, egg, or wheat, respectively, responded negatively to the open OFC test, and these differences were not statistically significant. In all three food allergen groups, skin-mucosal symptoms were the most common finding which was indicative of a positive response to the open OFC test.

The open OFC test results in children with a positive SPT to cow milk, egg or wheat indicated a relatively high failure rate of the test in the children. We recommend attention to food sensitivities in the evaluation of these patients. After confirmation of food sensitivities by existing methods; it is necessary to prevent consumption of these allergens and observe safety tips when dealing with these allergens