Trends in Seafood-Induced Anaphylaxis: Data From the European Anaphylaxis Registry

Shellfish and fish are increasingly consumed worldwide and are common triggers of food-induced anaphylaxis.

To characterize seafood-induced anaphylaxis using data from the European Anaphylaxis Registry.

Seafood-induced cases were selected from the registry (2007-2022) and analyzed regarding age and geographic distribution, elicitors, clinical features, and time trends.

We identified 462 patients, including 316 (68%) with shellfish- and 146 (32%) with fish-induced anaphylaxis. In Europe, shellfish showed geographic differences and was the main elicitor of food-induced anaphylaxis in Italy and Spain. Shrimp accounted for 76% of shellfish reactions, whereas fish-induced anaphylaxis involved a broader range of species (eg, cod, 41%; salmon, 18%; and tuna, 8.2%). Shellfish anaphylaxis was more common in adults (76%), particularly women, was not life-threatening and presented with an atopy-independent phenotype. Reactions were frequently related to larger portion sizes (48%) and suspected cofactors. An increase in adult shellfish-induced anaphylaxis was observed over time. In contrast, fish anaphylaxis with mild severity was more frequent in children and adolescents (59%), occurred more often in boys, and was often triggered by small allergen amounts. A prior reaction to the same allergen was reported in 57% of patients. Adrenaline was administered in 33% of adult shellfish cases and 24% of fish anaphylaxis cases in children.

Fish- and shellfish-induced anaphylaxis show distinct patterns regarding age, sex, and clinical manifestation, but also geographic distribution. Shellfish reactions in adults are on rise in Europe. The underuse of adrenaline highlights the need for improved management strategies across all age groups.