Wash. U. allergist warns of a meat allergy on the rise in Missouri

This summer, Dr. Maya R. Jerath, a Washington University allergist at Barnes-Jewish Hospital, is seeing more patients with alpha-gal syndrome. The potentially life-threatening condition causes allergic reactions to red meat like beef and pork. Mammals like cows, sheep, and pigs produce a sugar molecule called alpha gal, and it appears that being bitten by certain ticks, including Lone Star ticks, can create an allergy to that molecule. Because of the uptick in cases in recent months, Jerath wants to spread awareness of the condition and offer guidance on how to recognize it and how to handle it. 

Symptoms may present differently for different people, but they can include abdominal pain, heartburn, indigestion, nausea or vomiting. In fact, I believe many people diagnosed with irritable bowel syndrome (IBS) may actually have AGS. Symptoms may progress to hives, breathing difficulties, and feeling like your throat is closing. In worst cases, blood pressure will fall and result in dizziness and passing out. If left untreated, these allergic reactions may be fatal. It doesn’t mean that every patient having a reaction will have a life-threatening reaction. But it is possible.

You mentioned that you believe many people diagnosed with IBS may actually have AGS.  Why is AGS so difficult to diagnose? It is difficult because traditional food allergies happen immediately after exposure to particular foods and are 100 percent reproducible. This makes it easier to make the association. With AGS, reactions occur four-to-six hours later and people do not have the same reaction every time they eat meat—and they may not react at all. For instance, you can eat a burger three different times and have no reaction the first time, a severe reaction the second time, and then have no reaction the third time. This makes it extremely difficult to make the connection. Often times patients come in only after the life-threatening reaction.

Is the best way to avoid AGS to avoid getting bitten by ticks? To be clear, we are not 100 percent sure what causes it. Something that bites you seems to trigger this reaction. The Lone Star tick has been implicated in a large number of cases in the United States. But AGS has also been reported in many other countries, including Australia and France, where the Lone Star tick is not found. Other than avoiding tick bites, we don’t know any other way to avoid AGS at this point.

What are the best ways to avoid tick bites? Wear long sleeves and tuck your pants into your socks when you are in places where there is long grass and lots of ticks. Use insect repellant and check yourself for ticks when coming back from being outdoors or camping.  

If someone develops AGS, will they have it for the rest of their life? Not necessarily. You can outgrow it, but the number of people who have done so is small. The allergy appears to keep going if you continue getting tick bites. People who live in rural areas and spend lots of time outdoors are more at risk. The people who’ve outgrown AGS are those who have stopped getting tick bites.

What should you do if you think you have AGS? Seek evaluation by an allergist. AGS is diagnosed by looking at your clinical history and taking a blood test. Most people who have it will be fine if they avoid red meat like beef and pork. Stick to poultry, fish and shellfish. It doesn’t have to be a scary, horrible condition. Once you know you have it and how to manage it, you can live a normal life.