TOPLINE

Skin prick tests (SPTs) to allergen extracts or native food allergens and specific immunoglobulin E (sIgE) levels were moderately useful, with variable performance, for predicting oral food challenge (OFC) outcomes in patients with cow’s milk or hen’s egg allergy.

METHODOLOGY

• Researchers retrospectively reviewed data for children (range of median age, 5-6.1 years) who underwent OFC for baked milk (n = 42; 35.7% girls), raw milk (n = 43; 27.9% girls), baked egg (n = 54; 37.0% girls), or boiled egg (n = 54; 25.9% girls) at a pediatric hospital in Poland between 2023 and 2025.
• The children underwent SPTs using commercial extracts and fresh food samples such as fresh milk, raw egg white, and raw egg yolk, as well as blood tests for food-sIgE measurements using the ImmunoCAP and ALEX2 platforms within 6 months prior to OFCs.
• The OFC tests were conducted in a hospital setting as open challenges. The amount of food was slowly increased every 30 minutes until either an allergic reaction occurred or the child consumed a full age-appropriate serving.
• The area under the curve (AUC) values were used to assess how well each test distinguished children with allergy from those without the condition.

TAKEAWAY

• For baked milk allergy, casein-sIgE levels measured using ImmunoCAP had the highest AUC of 0.842 (95% CI, 0.709-0.975). At an optimal cutoff of 5.27 kUA/L, the test correctly identified all children with baked milk allergy (sensitivity, 100%).
• For raw milk allergy, beta-lactoglobulin-sIgE levels measured using ALEX2 worked best, with an AUC of 0.733. Alpha-lactalbumin-sIgE levels measured using ImmunoCAP also performed well, with an AUC of 0.726, a specificity of 90%, and a positive likelihood ratio of 5.91.
• For boiled egg allergy, the SPT using raw egg yolk yielded the highest AUC of 0.738, followed by egg white extract-sIgE and ovomucoid-sIgE with AUCs of 0.735 and 0.713, respectively, all measured using ALEX2.
• For baked egg allergy, ovalbumin-sIgE measured using ALEX2 was the strongest predictor with AUC of 0.853. Ovotransferrin-sIgE also worked reasonably well, with an AUC of 0.772, and SPTs to egg white extract had an AUC of 0.762.

IN PRACTICE

“[The study findings] suggest that although SPT and sIgE testing remain useful tools in the diagnostic workup of CM [cow’s milk] and HE [hen’s egg] allergy, their diagnostic performance is limited and should be interpreted in the context of the overall clinical picture,” the authors wrote.

SOURCE

Maria Wawszczak, MD, with the Medical University of Warsaw in Warsaw, Poland, was the corresponding author of the study, which was published online on July 3 in Nutrients.

LIMITATIONS

The study was conducted using past records, and the sample size was small, which reduced the strength of the results and led to wide CIs for several measures. The study group was also affected by spectrum bias because the children referred for OFCs were a selected group with suspected food allergy rather than a general group of children with possible food allergy.

DISCLOSURES

The study did not receive any external funding. The authors declared having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.