DIAGNOSTIC ACCURACY OF ALLERGEN COMPONENT SIGE IN CHILDHOOD PEANUT AND HAZELNUT ALLERGY: META ANALYSIS RESULTS

Introduction Specific IgE antibodies to peanut and hazelnut allergen components can help distinguish between symptomatic and clinically irrelevant sensitizations. We investigated the utility of peanut and hazelnut components in allergy diagnosis through a systematic approach, analyzing the diagnostic accuracy of sIgE to storage proteins and pollen cross-reactive PR-10 proteins. Methods Seven databases were searched for studies involving the diagnosis of patients suspected of peanut or hazelnut allergy and employing oral food challenges as reference standard. Study quality was assessed with QUADAS-2 tool. Diagnostic parameters of component-sIgE at several pre-defined cut-offs were calculated by meta-regression analysis of the data extracted. Results In total, 11/23 studies (peanut =17, hazelnut = 7) presented data suitable for meta-regression analysis, and were judged to have no concerns of applicability. The pooled sensitivity and specificity of Ara h 2-sIgE in single-gate pediatric studies was 85.8% and 83.6%, respectively at 0.35 kUA/L. The corresponding values of sIgE to hazelnut Cor a 14 and Cor a 9 were 81.7% / 77.9% and 77.6 / 67.3%, respectively. The diagnostic accuracy of peanut Ara h 2- sIgE and hazelnut Cor a 14-sIgE was found to be highest at 0.35 kUA/L threshold, while the optimal cut-off for hazelnut Cor a 9-sIgE was 1.0 kUA/L. Specific IgE to Ara h 8 and Cor a 1 PR-10 proteins had low diagnostic accuracy. Conclusions sIgE to storage proteins confer high specificity in diagnosing peanut and hazelnut allergy in children and may help in reducing the need for oral food challenges in diagnosing these allergies.