Tool shows utility in assessing differences in severity of food allergic reactions

The Food Allergy Severity Score, or FASS, quantified differences in the severity of allergic reactions to animal-source foods and to tree nuts and legumes, according to data from the EuroPrevall study.

The findings, presented at the European Academy of Allergy and Clinical Immunology Hybrid Congress, showed that when analyzing foods of animal origin, crustaceans and fish appeared more likely to elicit severe reactions, whereas in the analysis of tree nuts and legumes, peanuts induced reactions of higher severity.

“FASS seems to be a useful tool to assess differences in severity of food allergic reactions,” Rosialzira Natasha Vera-Berrios, allergist and internal medicine specialist with the allergy research group at Instituto de Investigación Sanitaria del Hospital Clínico in San Carlos in Madrid, Spain, said during her presentation on animal-source foods.

Because cow’s milk, hen’s egg, fish and shellfish, as well as tree nuts and peanuts, are frequent causes of allergic reactions and anaphylaxis, researchers aimed to describe the differences in the severity of reactions among them and in different geographical locations across Europe.

Researchers used FASS to score the severity of 8,232 immediate food reactions of patients presenting at 12 allergy referral centers across Europe. FASS uses ordinal (oFASS) and numerical (nFASS) formats to score reactions as mild (oFASS grade 1; nFASS 1.07-1.14), moderate (oFASS grade 2 and grade 3; nFASS 2.01-3.98) or severe (oFASS grade 4 and grade 5; nFASS 4.07-7.75).

Animal-source foods

In one part of the study, Vera-Berrios and colleagues analyzed data from 1,162 (14.1) of these reactions, which occurred to milk (n = 308), egg (n = 279), fish (n = 245), crustaceans (n = 240), mollusks (n = 49) and meats (n = 43). Researchers noted that the median age of patients reacting to milk (9.8 years) and egg (10.6 years) were younger than those reacting to fish (25.8 years), crustaceans (30.6 years), mollusk (29.9 years) and meat (27.1 years).

Data from the Kruskal-Wallis test showed significant differences in the severity of allergic reactions to these foods (P < .01), with the median nFASS ranging from 2.66 for each milk and egg, to 3.13 for fish, 3.14 for meat, 3.28 for crustaceans and 3.51 for mollusks.

A post-hoc comparison showed milk reactions were less severe than those to fish (P = .01) and crustacean (P = .014). Egg reactions also appeared less severe than those to fish (P = .05).

When stratified by age, researchers noted the milk and fish reactions among pre-school age children were significantly less severe.

Researchers also observed significant differences in reactions among patients presenting to different centers, with the exception of those with reactions to mollusks and meats, which had lower prevalence overall.

Tree nuts, legumes

Of the 8,232 overall reactions, 1,429 (17.4%) occurred due to tree nuts and 695 (8.4%) to legumes. These included reactions to hazelnut (n = 658), peanut (n = 511), walnut (n = 482), soybean (n = 88), lentil (n = 49), pea (n = 21), chickpea (n = 13), bean (n = 13) and lupin (n = 1).

Results of the Kruskal-Wallis test showed difference in reactions among the tree nuts (P = .02) but not among the legumes. When stratified by age, peanut reactions were significantly more severe among school-age children.

Overall, peanut-induced reactions appeared to have the highest severity. Although reactions to pea were infrequent, they also tended to be severe, involving anaphylaxis with respiratory or cardiovascular involvement.

Again researchers found differences according to geographical location, with greater severity of reactions observed in Manchester and Prague.

“FASS helps us understand the spectrum of food allergy severity, an essential knowledge to guide the implementation of health policies improving the safety and quality of life of food-allergic patients,” Vera-Berrios said in a press release.

References:

• Vera-Berrios RN, et al. Severity of reactions to tree nuts, peanut and other legumes across Europe: data from the EuroPrevall study. Presented at: EAACI Hybrid Congress; July 1-3, 2022; Prague (hybrid meeting).
• Severity of reactions to tree nuts, peanut and other legumes across Europe: data from the EuroPrevall study. https://eaaci-cdn-annual2022-media.azureedge.net/media-library-uploads/16_Severity_of_reactions_to_tree_nuts_peanut_and_other_legumes_across_Europe_Data_from_the_Euro_Prevall_study_7f2df4db1e.pdf. Published July 1, 2022. Accessed July 8, 2022.
• Severity of animal-source food allergy across Europe: data from the EUROPREVALL study.
• https://eaaci-cdn-annual2022-media.azureedge.net/media-library-uploads/15_Severity_of_Animal_source_Food_Allergy_across_Europe_Data_from_the_EUROPREVALL_study_84c56be31a.pdf. Published July 1, 2022. Accessed July 8, 2022.