Abstract: Background: The European Academy of Allergy and Clinical Immunology’s (EAACI) is updating the Guidelines on Food Allergy Diagnosis. We aimed to undertake a systematic review of the literature with meta-analyses to assess the accuracy of diagnostic tests for IgE-mediated food allergy. Methods: We searched three databases (Cochrane CENTRAL (Trials), MEDLINE (OVID) and Embase (OVID)) for diagnostic test accuracy studies published between 1 st October 2012 and 30 th June 2021 according to a previously published protocol (CRD42021259186). We independently screened abstracts, extracted data from full-texts, and assessed risk of bias with QUADRAS 2 tool in duplicate. Meta analyses were undertaken for food-test combination where 3 or more studies were available. Results: 149 studies comprising 24,489 patients met the inclusion criteria and were generally heterogeneous. 60.4% of studies were in children ≤12 years of age, 54.3% undertaken in Europe, ≥95% conducted in a specialized pediatric or allergy clinical setting and all included oral food challenge in at least a percentage of enrolled patients, in 21.5% DBPCFC. Skin prick test (SPT) with fresh cow’s milk and raw egg had high sensitivity (90% and 94%) for milk and cooked egg allergies. Specific IgE to individual components had high specificity: Ara h 2 had 92%, Cor a 14 95%, Ana o 3 94%, casein 93%, ovomucoid 92/91% for the diagnosis of peanut, hazelnut, cashew, cow’s milk and raw/cooked egg allergies, respectively. BAT was highly specific for the diagnosis of peanut (90%) and sesame (93%) allergies. Conclusions: SPT and specific IgE to extracts had high sensitivity whereas specific IgE to components and BAT had high specificity to support the diagnosis of individual food allergies. PROSPERO registration: CRD42021259186 Funding: European Academy of Allergy (EAACI).

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Olfactory and gustatory dysfunctions (OGD) have been reported as relevant symptoms that may predict presence of coronavirus disease 2019 (COVID-19) in adults, associated with mild or moderate disease1, 2, 3. However, published data on OGD in children are scant, likely due to several factors specific to the pediatric population such as a lower incidence of infection, the tendency of COVID-19 to be asymptomatic4, 5, and the difficulty of studying childhood OGD with objective methods. Two case reports have been published to date: one with 3 adolescents6, and the other describing a 17-year-old girl with beta-thalassemia who presented total loss of smell and taste for 8 days7 . Current data on the prevalence of OGD are based on only 2 small cohorts of COVID-19–positive children8, 9. In a related study, Mannheim et al.10 describe that 19 (30%) of 64 infected children (0–17 years old) presented nasal congestion, rhinorrhea, and total loss of smell, though providing no data on the exact number of patients with olfactory dysfunction exclusively.