Food allergy severity across the world: A World Allergy Organization international survey

Data on severity of food allergy across nations are lacking. Building on the World Allergy Organization (WAO) DEFASE (Definition of Food Allergy Severity) score, we aim to explore its global applicability as a grading system for IgE-mediated food allergy (FA) severity.

An international survey (WAO FASE Project) was conducted using an online questionnaire distributed to WAO members. The survey collected detailed data on diagnostic practices, therapeutic options, characteristics of FA patients, severity of reactions (including anaphylaxis), and eliciting doses of allergenic foods. In addition, FA management costs were examined (medical expenses, medication costs, and impact on quality of life and productivity).

We obtained information from 157 centers in 50 countries. FA management varied significantly across regions. Oral immunotherapy and omalizumab are widely used in Europe and North America. The use of advanced diagnostic tests (molecular diagnostics) vary widely between these regions. Thirty-five percent of patients with anaphylaxis exhibited severe symptoms (respiratory or cardiovascular compromise), with marked regional differences: more frequent in Western Asia (55.83%), Southern Africa (50%), and less frequent in South-Eastern Asia (12.5%) and Central America (21.72%). Approximately 1 in 4 patients reacted to less than half an age-appropriate portion of the allergenic food. Depending on the region, peanut, milk, egg, wheat, hazelnut, and peach allergies varied considerably. Economic resources and healthcare systems play an important role in determining access to diagnostic tests and therapeutic options, which have a direct impact on the severity and management of FA.

With wide global disparities in access to diagnostic and therapeutic tools for food allergies, this condition entails a vast healthcare and economic commitment. The percentage of patients receiving a high severity diagnosis using DEFASE could be around 3%, similar to that of asthma patients diagnosed with severe refractory asthma.