Introduction. Tropomyosin is considered to be the major antigen of shrimp and other shellfish, able to provoke IgE-mediated hypersensitivity reactions. This allergen is also known to be cross-reactive, as it is homologous between multiple species.
Case presentation. 27-year-old female had multiple anaphylaxis due to different triggers each time (consumption of shrimps, peanuts and pastry with white wine) and history of childhood asthma. Skin-prick and prick-prick testing showed positive results for shrimp, but were negative for inhalant allergens and peanut. Further testing with ALEX showed increased total serum IgE concentration, as well as sensitization to 19 allergens: strong sensitization to house dust and food mites, fish and seafood, moderate - to cockroaches and slight - to mold and yeast allergen group. Also, strong sensitization to cross-reactive tropomyosin was found. Treatment plan includes avoiding seafood, house dust mites and cockroaches, usage of allergy diary MASK to track symptoms of rhinitis.
Discussion. Tropomyosin is considered to be an invertebrate panallergen, due to its highly conserved structure between multiple species. It is known, that childhood asthma is a risk factor for sensitization to HDMs and cockroaches, and children with this condition have high prevalence of environmental allergies, specifically to indoor allergens. Our case report presents patient’s sensitization to four tropomyosin homologues between multiple species - shrimp, house dust mites, fish parasite Anisakis simplex and cockroach. It is possible that sensitization to all 19 allergens is due to tropomyosin.