Phadia’s nGal d2 test makes it possible to detect in the blood the IgE (antibody) responsible for allergic reactions to the ovalbumin in egg whites. Ovalbumin is the most abundant protein in egg whites and is sensitive to heat (cooking). Some vaccines are produced in chicken embryos and may contain small amounts of ovalbumin. The interpretation chart accompanying the result expresses the likelihood of an allergic reaction specific to the egg white ovalbumin, but not necessarily the severity of the reaction. Case history (age, symptoms, relation to meals, etc.) and clinical examination by the physician are essential for a reliable interpretation of the results.
An anti-nGal d2 IgE result of less than 0.35 kilounits per litre (< 0.35 kU/L) indicates that the ovalbumin is not likely to be responsible for the symptoms observed when eating cooked or raw eggs, but DOES NOT COMPLETELY ELIMINATE THIS POSSIBILITY. When the result is negative for nGal d1, a positive result for nGal d2 indicates a risk of allergic reaction to raw, lightly cooked eggs or certain vaccines. Both negative and positive results of molecular egg white allergen tests should be interpreted according to clinical manifestations. The double-blind oral food challenge remains the definitive technique for confirming any food allergy including one to raw or cooked egg.