Molecular diagnosis of cow's milk allergy

To identify and discuss studies on the molecular diagnosis of cow's milk allergy (CMA) with a view to update allergists since a general review of the methodology in 2006.

Seven basic research studies reporting the use of component-resolved diagnostics in CMA were found. All studies were on children positively reacting to a formal challenge with cow's milk. Six studies used natural allergens and three used recombinant milk proteins. Microarray platforms were customized and, thus, differed across studies. Three studies assessed the association between molecular-scale patterns and different presentations of the condition, that is the association between anaphylaxis, gastrointestinal symptoms and other severe phenotypes and the pattern of protein sensitization. Two studies assessed the association between positive oral food challenge and the persistence of milk allergy over time. Protein profiling could be useful to indicate appropriate specific immunotherapy.

Accurate diagnosis of CMA is challenging and essential. The determination of the immunoglobulin E (IgE)-mediated response to sequenced and characterized allergens may be more useful in predicting the presence and severity of clinical allergy than the currently used skin or blood tests performed with whole extracts. However, as component recognition pattern heterogeneity is observed in different areas, further clinical studies are essential to correlate useful molecular diagnostics and biological markers with disease and patient profiles. Until such markers are found and validated in different age groups, oral food challenge remains the reference standard for the diagnosis of CMA.