The Meat of the Matter: Understanding and Managing Alpha-Gal Syndrome

Abstract

Alpha-gal syndrome is an unconventional food allergy, characterized by IgE-mediated hypersensitivity responses to the glycan galactose-alpha-1,3-galactose (alpha-gal) and not to a food-protein. In this review, we discuss how alpha-gal syndrome reframes our current conception of the mechanisms of pathogenesis of food allergy. The development of alpha-gal IgE is associated with tick bites though the possibility of other parasites promoting sensitization to alpha-gal remains. We review the immune cell populations involved in the sensitization and effector phases of alpha-gal syndrome and describe the current understanding of why allergic responses to ingested alpha-gal can be delayed by several hours. We review the foundation of management in alpha-gal syndrome, namely avoidance, but also discuss the use of antihistamines, mast cell stabilizers, and the emerging role of complementary and alternative therapies, biological products, and oral immunotherapy in the management of this condition. Alpha-gal syndrome influences the safety and tolerability of medications and medical devices containing or derived from mammalian products and impacts quality of life well beyond food choices.

Alpha‐gal syndrome—Food or drug allergy: A case report

“…Despite avoidance, some people still have allergy symptoms. Their diet should be additionally altered because certain food additives include alpha‐gal 6,25 …”

“…Hence, oral immunotherapy with cow's milk has been explored. Further research is needed to determine alpha‐gal syndrome immunotherapy options 2,25 …”

“…Their diet should be additionally altered because certain food additives include alpha-gal. 6,25 Despite tolerating cooked red meat, we advised our patient to avoid any red meat. We wanted to minimize the danger of severe allergic responses, which might vary based on the kind of meat, alpha-gal content, and cofactors.…”

Management of Food Allergies and Food-Related Anaphylaxis

“…An alpha-gal IgE concentration of 0.1 kU/L or more is suggestive of the diagnosis, whereas an alphagal-specific IgE concentration lower than 0.1 kU/L is considered a negative result. 21,22,66,[87][88][89][90][91] In populations with high alpha-gal sensitization rates, alpha-gal IgE levels of at least 2 kU/L or more than 2% of the total IgE concentration increases the likelihood of a positive mammalian meat challenge to greater than 50%, 21,22,87 whereas values of at least 5.5 kU/L confer a 95% or more positive predictive value. 22 Primary Prevention of Food Allergy Randomized trials and meta-analyses have demonstrated that timely and consistent feeding of allergenic foods such as peanuts and eggs during infancy and into early childhood (Table ) is an effective primary prevention strategy against the development of food allergy, especially in infants with eczema.…”

“…[16][17][18][19][20] Other tick species associated with alphagal syndrome include Ixodes holocyclus, Amblyomma sculptum, Ixodes ricinus, and Haemaphysalis longicornis. 21 In contrast to the rapid onset of symptoms in food-protein allergy, symptoms from alpha-gal syndrome frequently appear 2 or more hours after ingesting mammalian meat (Figure 2), 4,5,17 although isolated gastrointestinal symptoms may occur sooner than 2 hours in some patients. 22,23 The reasons for delayed allergic symptom onset in alpha-gal syndrome are not completely understood.…”