Why is your patient suddenly allergic to hamburgers?

A patient may mention an incidental finding unrelated to psychotherapy that still affects their overall well-being. Consider Jim, for example.

Last week, Jim had no problem eating hamburgers or any other meat from mammals, but now he has vomiting, severe stomach pain, or diarrhea as part of an allergic reaction. This reaction could include other signs of allergy, such as hives, respiratory problems, and full-scale anaphylaxis. Jim’s allergic reaction did not happen right away. This made him wonder whether eating the hamburger caused the reaction.

Jim loves to hunt, fish, and hike in the woods. He was in great health the last time you saw him. Jim recently returned from a bird-watching trip to the southeastern US. There, he walked through woody brushy areas where the lone star tick (Amblyomma americanum) can aggressively bite hosts like deer and unsuspecting hikers.

Jim explains that it was so unseasonably hot for late Spring that he chose to wear shorts instead of his usual long clothing. Running late, he left the DEET bug spray in his Jeep. Jim related that the group’s guide hurried them off to lunch before he could check for ticks. He was surprised to find one later that day.

As a clinician, you may have seen this before in patients who were bitten while doing yard maintenance or pursuing their outdoor job as a landscaper or farmer. You would know to suspect Alpha-Gal Syndrome (AGS), sometimes called red meat allergy, and to order testing for specific immunoglobulin E (IgE) antibodies to alpha-gal.

How it works: In the United States, the lone star tick or the black-legged tick ( maybe even a chigger) injects the Alpha-Gal molecule into the body, and the body creates an antibody reaction to this molecule. The molecule is not only found in beef, but also in other mammalian meat, such as rabbit, pork, deer, and lamb. While mammalian meat is the main trigger, some people are triggered by dairy products or products containing gelatin, magnesium stearate, or glycerin that may have Alpha-Gal in them. Alpha-Gal is also found in some medications and biologics.

Outside the US, some other species of ticks may cause similar reactions.

So, what can you tell Jim to do?

–Learn the situations that risk tick bites, including common activities like cutting the grass

–Wear protective clothing in those settings

–Use bug spray

–Check for ticks when in areas known for ticks

–If there has been a past allergic reaction to tick bites, carry an Epi-Pen (an injectable device to administer epinephrine)

–Avoid wearing shorts or clothes that leave the body exposed

–Be informed about the ingredients in products and medications that may contain Alpha-Gal  

–Avoid eating mammalian meat

What can you tell Jim about his prognosis? How long this syndrome lasts varies, but it is ordinarily considered a long-term condition.  Being conscientious about avoiding triggers and future tick bites may or may not help improve the allergy or shorten the time for it to resolve. Sometimes, it is a lifelong condition.

I wanted to pass along this information to you, in case, like me, you had never heard of it before now, and you see a patient with these puzzling symptoms.

The more I learn about Alpha-Gal syndrome, the more I recognize how complex it is. For example, some intravenous medications with alpha-gal in them can cause more immediate allergic reactions in susceptible people. I hope this brief overview has piqued your interest to learn more.

I was more familiar with Lyme disease, another illness caused by a different kind of tick bite that has some different symptoms and outcomes.

To create this case study, I adapted information taken from articles from the Centers for Disease Control and Prevention (CDC), The Mayo Clinic, The Cleveland Clinic, and an article written by L Armstrong, “10 New and Surprising Facts About Alpha-Gal Syndrome.” ThermoFisher. July 1 2022.

Be safe. Jeff Duffey