Cases of unexplained anaphylaxis linked to red meat allergy

While rare, some people experience recurrent episodes of anaphylaxis — a life-threatening allergic reaction — for which the triggers are never identified. Recently, researchers found that some patients’ seemingly inexplicable anaphylaxis was actually caused by an uncommon allergy to a molecule found naturally in red meat. They note that the allergy, which is linked to a history of a specific type of tick bite, may be difficult for patients and health care teams to identify.