A Patient Experiencing Anaphylaxis and Urticaria, in Some Cases Preceded by Ingestion of Red Meat

Abstract

Question: I am evaluating a 51-year-old woman who lives in South Carolina. She reported 2 episodes of anaphylaxis that developed in the middle of the night and required treatment in the emergency department and several episodes of urticaria. Some of the episodes were preceded by ingestion of red meat 3 to 6 hours before the reactions. The symptoms started 9 months ago. Regarding the episodes of anaphylaxis, one occurred 6 hours after a meal of eggs with peppers and chicken, and she had no recollection of having red meat. The other episode was preceded by ingestion of red meat. During the latter episode, she awoke at 3:00 AM with generalized urticaria and was treated with 2 injections of epinephrine and Solu-Medrol. The hives resolved in a few hours. She had eaten beef for dinner at 9 PM that night. None of the episodes were preceded by an insect sting or bite or ingestion of any medications. She had not exercised before either episode. The patient also reports several episodes of itching, starting on the fingers and then spreading to involve the forearms. Sometimes this is associated with hives. Four of these episodes were preceded by ingestion of beef. Most reactions occur 3 to 6 hours after ingestion of red meat. She likes to hunt and reports at least 2 tick bites. One tick bite occurred a few years ago and caused a severe reaction, but she cannot remember details, except that she had to go to the hospital for treatment. She also had another tick bite several months ago which caused a large local reaction that persisted for weeks. She reports that handling shrimp causes swelling, but she tolerates ingestion of cooked shrimp. Nonetheless, she is currently avoiding shrimp and all red meat products and has not been having any episodes of hives, swelling, or anaphylaxis. The episodes of hives were not that frequent even before the change in her diet, so it is hard to say if the dietary elimination is working or not. She never had any problems with dairy, but because of an elevated specific IgE (see below) she is avoiding milk. She is wondering if she will be able to add it back into her diet at some point. She has been out hunting but reports no further tick bites. In addition, after talking to her some more recently, she reports hand swelling on some occasions in the past, always after doing a lot of dishes. I was thinking of vibratory or some sort of physical angioedema, but she also reports that some of the dishes had red meat on them, and she only had these episodes if she had cuts on her hands. Some of the episodes had associated hives, and one episode progressed to anaphylaxis (which led to an emergency department visit). She had not actually eaten any red meat that day. Skin tests were negative to beef, pork, and environmental allergens. Her laboratory results are as follows: IgE beef, 20.7 kUA/L; pork, 15.5 kUA/L; lamb, 3.08 kUA/L; milk, 2.98 kUA/L; cat, 4.48 kUA/L; dog, 2.75 kUA/L; and shrimp, 1.32 kUA/L. In addition, her bovine gelatin IgE was <0.35 and alpha-gal was 88 IU/mL. I have read the articles on alpha-gal allergy but was hoping for some help with the interpretation of these laboratory results. Thanks in advance.