Diagnosis progress in component-resolved diagnostics of food allergy / 中华实用儿科临床杂志

IgE-mediated food allergy is a common health problem worldwide, and the incidence of food allergy in China is also increasing gradually in the past decades.However, the traditional diagnostic measurements for food allergen specific IgE (sIgE) are based on the in- vivo or in- vitro tests of the intact allergen extracts, with low specificity and sensitivity, as well as limited diagnostic information.Therefore, the clinical diagnosis of food allergies often requires an oral food challenge test, which increases the suffering and risk of patients.Along with the development of component-resolved diagnostics (CRD) of food allergy, the sIgE against a single allergenic component can be measured quantitatively, thus generating the concept of " CRD" , which makes food allergy diagnosis more accurate and helps people distinguish cross allergens, determine the severity of the disease and the risk of severe allergic reactions, and predict the efficacy of immunotherapy.Besides, the diagnostic accuracy would be enhanced significantly and the reliance on oral food challenge tests would be reduced.In this review, the new progress in the diagnosis of common food allergen components would be summarized, and the advantages of CRD would be discussed.

Component-resolved diagnosis using microarray for diagnosing hypersensitivity to raw fruits in birch pollen sensitized children

PURPOSE: Recently, component-resolved diagnosis (CRD) using microarray technology has been introduced to the field of clinical allergy. This study was aimed to investigate the clinical usefulness of microarray-based IgE detection for diagnosing clinical raw fruit allergy in birch pollen-sensitized children. METHODS: Thirty-one children with allergic disease who had been sensitized to pollen were studied. A pollen-sensitized patient was defined as having an allergen-specific history with concomitant positive skin-prick tests (SPTs) to natural allergen extracts or positive allergen-specific IgE. All subjects underwent SPTs for pollen and fruit. In all subjects, specific IgE to pollen and fruit were measured by ImmunoCAP. Specific IgE antibodies to allergen components were determined by a customized allergen microarray (ISAC). RESULTS: Thirteen of the 31 patients (41.9%) had a history of fruit hypersensitivity with positive SPTs. Measuring IgE to allergen components by ISAC, all the 13 patients with fruit hypersensitivity were positive to at least one of Mal d 1, Pru p 1, Pru p 3, Act d 8, and Act d 2 compared to 12 of the 13 patients (92.3%) who had at least 1 positive IgE to fruits (apple, peach, and kiwi) using ImmunoCAP. The sensitivity of ISAC microarray was 100.0% for the diagnosis of fruit hypersensitivity, but its specificity was 27.7% (5/18). The sensitivity of ImmunoCAP was 92.3%, and its specificity was 83.3%. CONCLUSION: The sensitivity of allergen components tested using microarray for the diagnosis of clinical fruit hypersensitivity in children with pollen allergy was high; however, its specificity was low.