Phadia’s F202 test is used to detect blood levels of the IgE (antibodies) responsible for often very severe allergic reactions to cashews. Cashews have allergens in common with other nuts (pistachios, walnuts, hazelnuts) resulting in cross allergies. The interpretation chart accompanying the result expresses the probability of an allergic reaction to cashews, but not necessarily the severity of the reaction. Case history (symptoms, relation to meals, etc.) and clinical examination by the physician are essential for a reliable interpretation of the results.
A negative anti-cashew IgE result (< 0.35 kU/L) indicates that cashews are probably not responsible for the symptoms reported by the person, but it DOES NOT COMPLETELY RULE OUT THIS POSSIBILITY. All negative and positive results must be interpreted in light of the case history. The double-blind oral food challenge remains the definitive technique for confirming the presence or absence of a food allergy. In specific cases, detection of the anti Ana o3 IgE using molecular allergology can help establish a primary (rather than a cross) allergy to cashews. Unlike milk and egg white allergies, which many children outgrow, the hypersensitivity to cashews persists.