Drug allergens and food--the cetuximab and galactose-α-1,3-galactose story.
OBJECTIVE
A novel form of food allergy has been described that initially became apparent from IgE reactivity with the drug cetuximab. Ongoing work regarding the etiology, distribution, clinical management, and cellular mechanisms of the IgE response to the oligosaccharide galactose-α-1,3-galactose (α-gal) is reviewed.


METHODS
Brief review of the relevant literature in peer-reviewed journals.


METHODS
Studies on the clinical and immunologic features, pathogenesis, epidemiology, laboratory evaluation, and management of IgE to α-gal are included in this review.


RESULTS
Recent work has identified a novel IgE antibody response to the mammalian oligosaccharide epitope, α-gal, that has been associated with 2 distinct forms of anaphylaxis: (1) immediate-onset anaphylaxis during first exposure to intravenous cetuximab and (2) delayed-onset anaphylaxis 3 to 6 hours after ingestion of mammalian food products (eg, beef and pork). Study results have suggested that tick bites are a cause of IgE antibody responses to α-gal in the United States. Patients with IgE antibody to α-gal continue to emerge, and, increasingly, these cases involve children. Nevertheless, this IgE antibody response does not appear to pose a risk for asthma but may impair diagnostic testing in some situations.


CONCLUSIONS
The practicing physician should understand the symptoms, evaluation, and management when diagnosing delayed allergic reactions to mammalian meat from IgE to α-gal or when initiating treatment with cetuximab in patients who have developed an IgE antibody response to α-gal.
Department of Internal Medicine, Division of Allergy and Immunology, University of Virginia Health System, Charlottesville, Virginia.
Emily A
EA
Berg
Department of Internal Medicine, Division of Allergy and Immunology, University of Virginia Health System, Charlottesville, Virginia.
Thomas A E
TA
Platts-Mills
Department of Internal Medicine, Division of Allergy and Immunology, University of Virginia Health System, Charlottesville, Virginia; Department of Pediatrics, Division of Allergy and Immunology, University of Virginia Health System, Charlottesville, Virginia. Electronic address: spc7w@virginia.edu.
Scott P
SP
Commins
D000485:Allergens / Q000276:immunology* / Q000378:metabolism; D000818:Animals; D061067:Antibodies, Monoclonal, Humanized / Q000276:immunology* / Q000378:metabolism / Q000627:therapeutic use; D000068818:Cetuximab; D005512:Food Hypersensitivity / Q000209:etiology / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D016056:Immunodominant Epitopes / Q000276:immunology* / Q000378:metabolism; D007073:Immunoglobulin E / Q000096:biosynthesis* / Q000378:metabolism; D007074:Immunoglobulin G / Q000096:biosynthesis / Q000378:metabolism; D026863:Ixodidae / Q000276:immunology; D014312:Trisaccharides / Q000276:immunology* / Q000378:metabolism
D000485:Allergens; D061067:Antibodies, Monoclonal, Humanized; D016056:Immunodominant Epitopes; D007074:Immunoglobulin G; D014312:Trisaccharides; C076569:alpha-galactosyl epitope; D007073:Immunoglobulin E; D000068818:Cetuximab