Component-Resolved Diagnosis of Hazelnut Allergy in Children

Abstract

Hazelnuts commonly elicit allergic reactions starting from childhood and adolescence, with a rare resolution over time. The definite diagnosis of a hazelnut allergy relies on an oral food challenge. The role of component resolved diagnostics in reducing the need for oral food challenges in the diagnosis of hazelnut allergies is still debated. Therefore, three electronic databases were systematically searched for studies on the diagnostic accuracy of specific-IgE (sIgE) on hazelnut proteins for identifying children with a hazelnut allergy. Studies regarding IgE testing on at least one hazelnut allergen component in children whose final diagnosis was determined by oral food challenges or a suggestive history of serious symptoms due to a hazelnut allergy were included. Study quality was assessed by the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Eight studies enrolling 757 children, were identified. Overall, sensitivity, specificity, area under the curve and diagnostic odd ratio of Cor a 1 sIgE were lower than those of Cor a 9 and Cor a 14 sIge. When the test results were positive, the post-test probability of a hazelnut allergy was 34% for Cor a 1 sIgE, 60% for Cor a9 sIgE and 73% for Cor a 14 sIgE. When the test results were negative, the post-test probability of a hazelnut allergy was 55% for Cor a 1 sIgE, 16% for Cor a9 sIgE and 14% for Cor a 14 sIgE. Measurement of IgE levels to Cor a 9 and Cor a 14 might have the potential to improve specificity in detecting clinically tolerant children among hazelnut-sensitized ones, reducing the need to perform oral food challenges.

Oleosin Cor a 15 is a novel allergen for Italian hazelnut allergic children

“…Regarding the IgE levels, the Cor a 9 and Cor a 14 IgE levels were clearly associated with the elicitation of the allergic reaction, according to Datema et al, 21 and were useful to discriminate between the hazelnut‐allergic and hazelnut‐sensitized but tolerant patient groups. This was not found for the Cor a 1 and Cor a 8 IgE levels, for which a moderate diagnostic predictive value has been demonstrated 22 . The IgE levels of the newly discovered Cor a 15 seemed to have a similar behavior, as they were unable to discriminate between allergic and sensitized patients.…”

“…This was not found for the Cor a 1 and Cor a 8 IgE levels, for which a moderate diagnostic predictive value has been demonstrated. 22 The IgE levels of the newly discovered Cor a 15 seemed to have a similar behavior, as they were unable to discriminate between allergic and sensitized patients.…”

Title: Current options in the management of tree nut allergy, focusing on, but not limited to immunotherapy: A systematic review.

“…Sublingual immunotherapy has been investigated only for hazelnut allergy, with moderate efficacy but a favorable safety profile 14,34 . Nevertheless, the sample size was small, and the extract used was standardized for Cor a 1 (PR-10) and Cor a 8 (LTP) allergens, and not for Cor a 9 (legumin) or Cor a 14 (2S albumin), which better predict severe hazelnut allergy 39,40 . LTP allergy has an extremely variable clinical presentation 41 , which could explain the loss of protection described in one patient in the follow-up study after he had tolerated the highest dose in the original study.…”

“…The population in question was adults in five studies 16,17,28,36,38 , children in eleven 14,[23][24][25][31][32][33][34][35]37,39 , and both in eight 15,18,21,22,26,27,29,30 . Two studies were addressed to the caregivers of children 19,20 .…”

Developments in pediatrics in 2020: choices in allergy, autoinflammatory disorders, critical care, endocrinology, genetics, infectious diseases, microbiota, neonatology, neurology, nutrition, ortopedics, respiratory tract illnesses and rheumatology

“…Unnecessary exhaled nitric oxide measurement [ 5 , 6 ] should be avoided and research studies on exhaled biomarkers [ 7 ] carefully conducted. Disposable filter, instrument sterilization, and personal protective equipment should be used during visits or other diagnostic procedures such as skin test to allergens [ 8 ] or blood sampling for IgE detection to inhalants [ 9 ] and foods [ 10 ] and for autologous serum skin test [ 11 ]. Anaphylaxis, food protein-induced enterocolitis syndrome, allergy to nutritionally essential foods, severe reactions to hymenoptera venoms, reactions to necessary drugs, severe eczema or asthma need a rapid allergy workup.…”