Alpha-Gal syndrome: Clinical presentation, new concepts, and unmet needs.

For decades, carbohydrate determinants were seen as cross-reactive structures without clinical impact. The discovery of specific IgE to the carbohydrate galactose-α-1,3-galactose, called α-gal, changed our perspective on the allergenic potential of carbohydrate determinants. α-Gal is present in tissues of non-primate mammals and, upon ingestion, can provoke a delayed form of allergic reaction in sensitized patients. We are faced with a new and unique entity of allergy with high clinical relevance in food allergy and anaphylaxis to drugs derived from mammalian products. Tick bites are assumed to constitute the primary sensitization source to α-gal. To address the complexity of this disease, the term α-gal syndrome has been suggested.