Anaphylaxis is a serious life-threatening allergic reaction that typically has an immediate onset. It can present as flushing, angioedema, shortness of breath, rash and result in death if not treated immediately. In the past ten years, an emerging cause of delayed anaphylaxis has been identified. An IgE antibody to a mammalian oligosaccharide epitope (alpha-gal, or galactose-alpha-1,3-galactose) has been linked to both immediate and delayed onset anaphylaxis. The immediate form is associated with the first exposure to cetuximab; whereas the delayed onset occurs after ingestion of mammalian meat such as beef and pork. The presentation can develop 2-6 hours after ingestion. This IgE antibody to alpha-gal is strongly suggested that Lone Star tick bites have been the culprit. It is imperative when caring for an anaphylaxis patient of unknown etiology, to consider a line of questioning to not only include recent tick bites, but also last 2-3 meals ingested to identify if mammalian meat may have been the trigger.
Delayed Anaphylaxis and Urticaria Associated with Eating Mammalian Meat: Are IgE Antibodies to a Common Carbohydrate Capable of Mediating Systemic Reactions?