Benefit of the basophil activation test in deciding when to reintroduce cow's milk in allergic children.

Abstract

BACKGROUND:

Oral challenges are required to establish the persistence or resolution of IgE-mediated cow's milk allergy (CMA). Determining the appropriate timing for challenging is the main difficulty. The benefit of the basophil activation test (BAT) in predicting a child's reaction to the oral challenge was evaluated and compared to the specific IgE and skin prick tests' (SPT) results.

METHODS:

One hundred and twelve consecutive children with CMA admitted for an oral challenge to reassess their allergy were included. Allergen-induced basophil activation was detected as a CD63-upregulation by flow cytometry.

RESULTS:

Thirty-six children (32%) had a positive oral challenge. The percentage of activated basophils in patients with a positive challenge (mean = 20.9; SD = 18.8) was significantly higher than that of patients with a negative challenge (mean = 3.9; SD = 9.8, P < 0.0001), and was well correlated with the eliciting dose of cow's milk (P < 0.0001). The BAT had an efficiency of 90%, a sensitivity of 91%, a specificity of 90%, and positive and negative predictive values of 81% and 96% in detecting persistently allergic patients. The area under the ROC curve was 0.866. These scores were higher than those obtained with SPT and IgE values, whichever positivity cut-point was chosen. Referring to a decisional algorithm combining BAT, specific IgE and SPT allowed the correct identification of 94% of patients as tolerant or persistently allergic to cow's milk proteins (CMP) in our cohort.

CONCLUSION:

The BAT could be a valuable tool in the management of paediatric CMA in addition to specific IgE quantification and SPT, by contributing in determining whether an oral challenge can safely be undertaken.

• Authors: A Rubio, M Vivinus-Nébot, T Bourrier, B Saggio, M Albertini, A Bernard
• Journal: Allergy (Allergy) Vol. 66 Issue 1 Pg. 92-100 (Jan 2011) ISSN: 1398-9995 [Electronic] Denmark
• PMID: 20608919 (Publication Type: Evaluation Study, Journal Article)
• Copyright: © 2010 John Wiley & Sons A/S.

Chemical References

• Immunoglobulin E

Topics

• Animals
• Basophil Degranulation Test (methods)
• Basophils (immunology)
• Child
• Child, Preschool
• Female
• Flow Cytometry
• Humans
• Hypersensitivity, Immediate (diagnosis, immunology)
• Immunoglobulin E (blood)
• Infant
• Male
• Milk (adverse effects, immunology)
• Milk Hypersensitivity (diagnosis, immunology)
• Predictive Value of Tests
• ROC Curve
• Sensitivity and Specificity
• Skin Tests