Diagnosis

Doctors can diagnose alpha-gal syndrome using a combination of your personal history and certain medical tests.

Your doctor will likely start by asking about your exposure to ticks, your signs and symptoms, and how long it took for symptoms to develop after you ate red meat. He or she might also perform a physical exam.

Additional tests used to diagnose alpha-gal syndrome are likely to include:

  • Blood test. A blood test can confirm and measure the amount of alpha-gal antibodies in your bloodstream. This is the key test for diagnosis of alpha-gal syndrome.
  • Skin test. Doctors prick your skin and expose it to small amounts of substances extracted from commercial or fresh red meat. If you're allergic, you develop a raised bump (hive) at the test site on your skin. Your doctor or allergist may also test your skin for an allergic reaction to individual types of red meat.

Treatment

As with any food allergy, alpha-gal syndrome treatment involves avoiding the foods that cause your reaction. Always check the ingredient labels on store-bought foods to make sure they don't contain red meat or meat-based ingredients. Check soup stock cubes, gravy packages and flavor ingredients in prepackaged products. Ask your doctor or allergist for a list of foods to avoid, including meat extracts used in flavoring. The names of some ingredients make them difficult to recognize as meat based.

Use extra caution when you eat at restaurants and social gatherings. Many people don't understand the seriousness of an allergic food reaction, and few realize meat allergies even exist — much less than even a small amount of red meat can cause a severe reaction.

If you are at all worried that a food may contain something you're allergic to, don't try it. Come prepared to social events to avoid risk of exposure. For example, if you're attending a party where guests prepare food on a shared cooking surface, bring your own precooked food.

For a severe allergic reaction, you may need an emergency injection of epinephrine and a visit to the emergency room. Many people with allergies carry an epinephrine autoinjector (EpiPen, Auvi-Q, others). This device is a syringe and concealed needle that injects a single dose of medication when pressed against the thigh. Once you've been diagnosed with alpha-gal syndrome, your doctor or allergist likely will prescribe an epinephrine autoinjector.

Symptoms of alpha-gal syndrome may lessen or even disappear over time if you don't get any more bites from ticks that carry alpha-gal. Some people with this condition have been able to eat red meat again after one to two years without additional bites.

Preparing for your appointment

To get the most from your appointment, it's a good idea to be well-prepared. Here's some information to help you get ready for your appointment, and to know what to expect from your doctor.

  • Description of your symptoms. Be ready to tell your doctor what happened after you ate red meat, including how long it took for a reaction to occur. Be prepared to describe the type of red meat you ate as well as the portion size.
  • History of tick bites or possible exposure to ticks. Your doctor will need to know where you've spent time outdoors and how often, as well as how many tick bites you're aware of having experienced.
  • Make a list of all medications you're taking. Include vitamins or supplements.
  • Take a family member or friend along, if possible. Sometimes it can be difficult to recall all the information provided to you during an appointment. Someone who comes with you may remember something you missed or forgot.
  • Write down any questions you have.

Some basic questions to ask your doctor include:

  • Are my symptoms likely caused by a red meat allergy?
  • What else might be causing my symptoms?
  • What tests do I need?
  • What's the best treatment?
  • Should I see a specialist?
  • Is there a generic alternative to the medicine you're prescribing?
  • Are there brochures or other printed material that I can take with me? What websites do you recommend?
  • Do I need to carry an epinephrine autoinjector?

What to expect from your doctor

Your doctor is likely to ask you a number of questions, including:

  • When did you begin noticing symptoms?
  • What type of meat and how much did you eat before symptoms appeared?
  • After eating red meat, how long did it take symptoms to appear?
  • Are you currently spending time or have you in the past spent time outdoors in tick-infested areas?
  • Have you been bitten by a tick in the past? How many times? What did these ticks look like?
  • Did you take any over-the-counter allergy medications, such as antihistamines, and if so, did they help?
  • Does your reaction seem to be triggered only by red meat or by other foods as well?
  • How severe are your symptoms?
  • What, if anything, seems to improve your symptoms?
  • What, if anything, appears to worsen your symptoms?

What you can do in the meantime

If you suspect you have alpha-gal syndrome, avoid eating red meat until your doctor's appointment. If you have a severe reaction, seek emergency help.

June 12, 2018
References
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