Background and objective: Shellfish forms a common food source in the Asia-Pacific and is also growing in the West. This review aims to summarize the current literature on the epidemiology and research on shellfish allergy with particular focus on studies emerging from the Asia-Pacific region.
Data sources: A PubMed search using search strategies "Shellfish AND Allergy", "Shellfish Allergy Asia", and "Shellfish AND anaphylaxis" was made. In all, 244 articles written in English were reviewed.
Results: Shellfish allergy in the Asia-Pacific ranks among the highest in the world and is the most common cause of food-induced anaphylaxis. Shellfish are classified into molluscs and arthropods. Of the arthropods, the crustaceans in particular Penaeid prawns are the most common cause of allergy and are therefore most extensively studied. Several classes of allergens have been identified. The tropomyosins (class 1 allergens) are the best defined. Despite the establishment of molecular homology and allergenic cross reactivity between allergens of the same class, clinical cross-reactivity is more variable between patients and less clearly defined. There are two relatively unique clinical manifestations of IgE-mediated prawn allergy: (1) isolated oral allergy symptoms; and (2) wide spectrum of severity and sometimes even within the same individual.
Conclusion: Shellfish allergy is common in the Asia Pacific. More research including food challenge-proven subjects are required to establish the true prevalence, as well as to understand clinical cross reactivity and variations in clinical features.