Biomarkers Guide Baked Milk Tolerance in Allergic Kids

Medscape

12-05-2025

Introducing baked milk (BM) products carried some risk in children with cow's milk allergy (CMA), but biomarkers such as high casein–skin prick test, CA-specific immunoglobulin E (CM-sIgE), casein-sIgE, and certain ratios (alpha lactalbumin–sIgE/total IgE) may help identify children more likely to tolerate BM safely.
METHODOLOGY:
Researchers conducted a prospective interventional trial to assess biomarkers that can predict the safe introduction of BM in high-risk children with CMA.
They recruited 50 children (62% boys) aged 1 to ≤ 6 years with a history of CMA; these children's diets between June 2016 and December 2018 did not include BM or milk traces.
High casein-skin prick test for CM and components (casein, alpha-lactalbumin, beta-lactoglobulin), CM-sIgE, CM-sIgG4, and a basophil activation test were performed at diagnosis.
The children underwent a BM–oral food challenge (BM-OFC) targeting a 1-g cumulative dose of CM protein. Those who tolerated the BM-OFC underwent CM-OFC to confirm their CMA status.
TAKEAWAY:
A casein-sIgE level < 5.7 kU/L predicted BM tolerance, with sensitivity and specificity of 72% and 88%, respectively. A CM-sIgE level < 8.5 kU/L also predicted BM tolerance, with both sensitivity and specificity being 72%.
A casein-skin prick test wheal size of ≤ 5 mm, an alpha-lactalbumin-sIgE/total IgE ratio of ≤ 0.05, and a casein-sIgG4/casein-sIgE ratio of ≤ 0.1 were predictors of tolerance in the BM-OFC, with good sensitivity and specificity.
Significant differences were recorded in the basophil activation test 'net' analysis, where patients allergic to BM had a higher percentage of CD63+ cells than those tolerant to BM ( P = .0227) when basophils were stimulated with 0.001 mg/mL of CM.
IN PRACTICE:
'A combination of biomarkers and clinical history, especially a previous history of anaphylaxis with baked or hidden allergens, is likely to aid in distinguishing highly reactive patients,' the authors of the study wrote. 'A CM-sIgE level lower than 8.5 kUA/L and/or casein-sIgE level lower than 5.7 kUA/L can help to predict tolerance.'
SOURCE:
Domínguez O, PhD, with the Hospital Sant Joan de Déu, Barcelona, Spain, was the lead author of the study, which was published online on May 5 in Journal of Investigational Allergology and Clinical Immunology .
LIMITATIONS:
The sample size of this study was relatively small. Physicians chose the medication during OFCs, which may have resulted in treatment variations among children.
DISCLOSURES:
This study received funding from the Spanish Pediatric Society of Allergy, Asthma, and Clinical Immunology and the Catalan Society of Allergy and Clinical Immunology. The authors reported having no conflicts of interest.