(HealthDay News) – Individuals who have been bitten by the lone star tick may develop immunoglobulin E (IgE) to the carbohydrate galactose-α-1,3-galactose (alpha-gal), which puts them at risk for delayed anaphylaxis after consumption of meat containing alpha-gal on glycoproteins or glycolipids, according to a study published online July 20 in the Journal of General Internal Medicine.
Susan E. Wolver, MD, from the Virginia Commonwealth University in Richmond, and colleagues described three clinical cases of delayed anaphylaxis linked to the ingestion of red meat.
The researchers note that all three patients had a history of hives and/or anaphylaxis. All three developed hives and anaphylaxis three to six hours after eating mammalian meat (beef). Two of the patients recalled being bitten by a tick – one recently and one many years earlier. In one patient, a skin prick test produced negative results for beef and pork. Laboratory tests revealed IgE to alpha-gal and specific IgE to beef and pork.
“In summary, particularly in the southeastern United States where ticks are endemic, clinicians should be aware of this new syndrome when presented with a case of anaphylaxis,” the authors write. “Clinical history is key in solving these mystery cases, and a positive test for IgE against alpha-gal can help confirm the suspected diagnosis. Prevention of future life-threatening events requires dietary avoidance of all mammalian meat.”