Food Allergies and Alpha-gal Syndrome for the Gastroenterologist

Curr Gastroenterol Rep. 2023 Feb;25(2):21-30. doi: 10.1007/s11894-022-00860-7. Epub 2023 Jan 27.

Abstract

Purpose of review: Food allergies are typically not considered as a cause of gastrointestinal (GI) distress without additional allergic symptoms, apart from celiac disease and eosinophilic esophagitis. However, recent reports of patients with alpha-gal syndrome who presented with GI-only symptoms like abdominal pain, vomiting, and diarrhea challenge this paradigm. Alpha-gal syndrome is an IgE-mediated allergy characterized by delayed reactions after eating mammalian meat or mammalian-derived products that contain galactose-alpha-1,3-galactose (alpha-gal). The purpose of this review is to discuss our current understanding of food allergies, GI illness, and the GI manifestations of alpha-gal syndrome.

Recent findings: Among Southeastern U.S. GI clinic patients who screened positive for serum alpha-gal IgE, a majority of patients reported significant symptom improvement on an alpha-gal-avoidant diet, suggesting that the allergy had played a role in their GI symptoms. Diagnosis of alpha-gal syndrome is typically made with concerning allergic symptoms, elevated alpha-gal specific IgE in the serum, and symptom improvement on an alpha-gal avoidant diet. Alpha-gal syndrome can cause a delayed allergic response that is increasingly recognized worldwide, including among patients with predominant GI symptoms.

Keywords: Alpha-gal syndrome; Gastrointestinal; Mammalian meat allergy; Red meat allergy; Tick.

Publication types

  • Review

MeSH terms

  • Animals
  • Food Hypersensitivity* / complications
  • Food Hypersensitivity* / diagnosis
  • Galactose
  • Gastroenterologists*
  • Humans
  • Immunoglobulin E
  • Mammals
  • Syndrome

Substances

  • Galactose
  • Immunoglobulin E

Supplementary concepts

  • red meat allergy