Molecular insights and emerging therapies in shrimp & fish allergy: Contrasting perspectives from Asia and the West.

Seafood allergy is a global health concern with substantial geographic variation in prevalence. This review examines molecular diagnostics and emerging therapies for shrimp and fish allergies, highlighting contrasting perspectives between Asian and Western populations in allergen sensitization profiles, clinical phenotypes, diagnostic performance, and therapeutic development. In shrimp allergy, tropomyosin (TM) is a major allergen recognized by 50-80% of patients. TM's high structural conservation underlies IgE-mediated cross-reactivity among crustaceans, insects, and mites, complicating diagnostic testing. Non-TM allergens including Arginine Kinase (AK), Myosin Light Chain (MLC), Sarcoplasmic Calcium-Binding Protein (SCBP), and Hemocyanin (Hc) contribute substantially to sensitization, particularly in Asian pediatric cohorts. In contrast, Western populations demonstrate predominant TM sensitization. In fish allergy, beta-parvalbumin is the predominant allergen, conferring extensive cross-reactivity across bony fish species. However, minor allergens such as beta-enolase, aldolase A, and collagen are clinically relevant, especially in parvalbumin-negative cases. Component-resolved diagnosis (CRD) is essential for diagnostic precision, particularly in selective fish allergies. IgE cross-reactivity with TM leads to false-positive results on skin prick tests (SPT) and specific IgE (sIgE) testing. Immunotherapy is an emerging therapeutic option. Oral Immunotherapy (OIT) for shrimp and fish has demonstrated promising results. Sublingual Immunotherapy (SLIT) offers a potentially safer alternative approach. Omalizumab may facilitate OIT in high-risk patients. Knowledge gaps remain regarding extract standardization, population-specific diagnostic algorithms and cutoffs, and the clinical relevance of emerging allergens, highlighting priorities for advancing personalized diagnosis and treatment across diverse global populations.