Allergy To Limanda aspera (Yellowfin Sole): Report of a Case of Food Allergy in a Child

Clinical Relevance of Cross-Reactivity in Food Allergy

The diagnosis and management of food allergy is complicated by an abundance of homologous, cross-reactive proteins in edible foods and aeroallergens. This results in patients having allergic sensitization (positive tests) to many biologically related foods. However, many are sensitized to foods without exhibiting clinical reactivity. Although molecular diagnostics have improved our ability to identify clinically relevant cross-reactivity, the optimal approach to patients requires an understanding of the epidemiology of clinically relevant cross-reactivity, as well as the food-specific (degree of homology, protein stability, abundance) and patient-specific factors (immune response, augmentation factors) that determine clinical relevance. Examples of food families with high rates of cross-reactivity include mammalian milks, eggs, fish, and shellfish. Low rates are noted for grains (wheat, barley, rye), and rates of cross-reactivity are variable for most other foods. This review discusses clinically relevant cross-reactivity related to the aforementioned food groups as well as seeds, legumes (including peanut, soy, chickpea, lentil, and others), tree nuts, meats, fruits and vegetables (including the lipid transfer protein syndrome), and latex. The complicating factor of addressing co-allergy, for example, the risks of allergy to both peanut and tree nuts among atopic patients, is also discussed. Considerations for an approach to individual patient care are highlighted.

Fish Allergy Management: From Component-Resolved Diagnosis to Unmet Diagnostic Needs

Purpose of review

Fish is a common elicitor of IgE-mediated food allergy. Fish includes a large variety of foods, in terms of species and food processing, with marked distinction in local diets around the globe. Fish-allergic patients present with phenotypic diversity and major differences in levels of clinical cross-reactivity, features that pose an important challenge for the clinical diagnosis and management.

Recent findings

Parvalbumin is the major fish allergen. However, a single molecule is not sufficient but several homologs, allergens different from parvalbumin and allergen extracts, are needed for IgE-based diagnosis.

Summary

Parvalbumin-specific IgE are markers for clinical cross-reactions. Added value is provided by IgE typing to parvalbumin homologs from distantly related fish. IgE co-sensitization profiles (parvalbumin, enolase, aldolase) are referred as severity markers. The allergen panel seems to be not yet complete why fish extracts still play a crucial role in serum IgE analysis. Further clinical validation of a multiplex approach in molecular fish allergy diagnosis is needed for striving to avoid unnecessary food restrictions and in a further sense, improved patient care.