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Ice Cream Therapy

Ice Cream Therapy

Finally, a medical therapy I can relate to.  I love ice cream.  Actually, it’s not a medical therapy, but a safe mechanism to “test the waters” in alpha-gal syndrome.  This newsletter has previously discussed this uncommon condition that unfortunately is becoming more common.  By way of reminder the syndrome is the new onset of anaphylaxis due to eating meat.  It is a strange condition in that the allergic symptoms occur suddenly (hives, swelling, throat constriction) but are delayed 3 to 6 hours from the meat ingestion.  It’s kind of similar to touching a hot stove and then feeling the sudden pain hours later.  The reason it develops is due to allergic sensitization from a tick bite.  The other peculiar aspect of the syndrome is that the allergic issue usually doesn’t develop for several months after the tick bite.  Thus, people often don’t associate the two.  The tick saliva contains a molecule called alpha-gal which is also found in meat, especially beef and pork.  The diagnostic test is to draw blood and see if there are antibodies to alpha-gal.  An antibody level greater than .10 IU/L makes the diagnosis “possible” and a level greater than 2 IU/L is definitive. 

If a patient avoids further tick bites this antibody level can decrease over time.  Once it has decreased enough then the likelihood for reaction goes away.  So it is in this setting that the ice cream test comes in to play.  High fat ice cream has a very small amount of alpha-gal, so if ingesting it turns out to be safe, then the patient can feel greater comfort returning to meat. 

I guess I can justify my nightly ice cream dessert as a proof that I’m not developing alpha-gal.

Alpha-gal Revisited

Alpha-gal Revisited

Several years ago, this newsletter discussed a new form of anaphylaxis due to tick bites.  The syndrome is peculiar in several ways.  Most importantly the anaphylaxis is delayed from the exposure by several hours.  Also, it occurs after eating mammalian meat such as beef and pork. 

Alpha-gal is a glycoprotein that is found in mammalian meats.  The patient becomes sensitized to the alpha-gal from a tick bite because the ticks secrete alpha-gal in their saliva when they bite humans.  In order to diagnose the condition, the patient needs to be tested for alpha-gal.  They do not show a positive response to the standard allergy tests for beef, pork, etc. 

The new twist is that certain round worms, such as Ascaris lumbricoides also contain alpha-gal and infestation with these worms can lead to the same syndrome.