People who experience recurrent severe allergic reactions known as anaphylaxis that have no apparent cause may be allergic to meat. According to a new study, which was presented at the 2010 Annual Meeting of the American Academy of Allergy, Asthma & Immunology (AAAI), a carbohydrate in meat called alpha-gal may be causing such severe allergic reactions in some individuals.
Some people who have an anaphylactic reaction to something unknown that they have eaten are at an increased risk for experiencing more episodes if they are not able to identify what triggered their attack. Previous research indicates that people who have IgE (immunoglobulin E) to alpha-gal report experience anaphylaxis or hives three to six hours after consuming mammalian meat. Therefore a team of investigators decided to explore how many cases of anaphylaxis of unknown cause may be triggered by eating meat.
A total of 60 people in the United States and Australia who experienced anaphylaxis with no known cause were evaluated. All participants underwent allergy tests, which revealed that 25 of the 60 patients had positive responses to alpha-gal. The tests did not identify any other allergens that would have explained the severe allergic reactions in the 25 patients who were positive for alpha-gal or in the other 35 patients.
According to the American Academy of Allergy, Asthma & Immunology, approximately 3 million children younger than 18 years were reported to have a food or digestive allergy in the previous 12 months, and more than 3 percent of adults have one or more food allergies. The AAAI also notes that food allergies account for 35 to 50 percent of all cases of anaphylaxis, and that food allergies cause approximately 150 to 200 deaths per year, based on a 2003 study from the Mayo Clinic.
Dr. Scott P. Commins, of the University of Virginia and one of the AAAI study’s authors, notes that previous research and the current study “continue to suggest not only that IgE to a carbohydrate has important clinical implications in food allergy and anaphylaxis, but that the presence of this antibody may well have been under appreciated in terms of the number of patients affected and geographical scope.” Therefore, there may be more people allergic to meat than previously thought.
American Academy of Allergy, Asthma & Immunology
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