Friday, September 7, 2012

Fifty Shades of Egg

At the end of April, I shared Egg-cellent news that JR, my 4 year old son, successfully ate one half of a hard-boiled egg during a food challenge at the allergist's office (see previous post for a detailed description of a food challenge).  As parents, we were beyond thrilled, since it appeared that JR had outgrown his egg allergy!  In a long list of food allergies, egg is one that I will happily check off the list.

However, there was a remote possibility that JR's egg allergy could return with a vengeance following the egg exposure at the food challenge.  Before the egg challenge, JR's last known exposure to egg had been as an ~18 month old, and the reaction had been anaphylactic (for description of anaphylaxis, see the Allergist Mom's post).  Needless to say, nothing strikes fear into a food allergy parent more than anaphylaxis, the most severe, lightning fast (usually), and life-threatening kind of reaction which involves several bodily systems.

Because of this possibility, we were to wait at least a month and follow up with a blood test to look for the specific antibodies to egg in JR's blood that could cause an allergic reaction.  Because it had been so long since JR's last egg exposure, the level of antibodies to egg may have fallen below what the blood test could reliably detect.  This means that the first exposure to egg would not trigger a reaction.  With more time (e.g. weeks), however, JR's immune system may have mounted a "defense" against the egg he just ate. Meaning, antibody production would increase so that the immune system may respond if exposed again (Side note:  normally this is a brilliant process to protect from invading bacteria/viruses/etc that cause illness.  Our immune system learns to fight them off, so we don't fall ill to the same bad "bugs" again).  If the amount of antibody in JR's blood did not change, then we were in the clear, meaning the egg allergy had indeed gone away.  However, if the amount of antibody in JR's blood increased above its last tested value, it could indicate that the allergy had returned.

So, we tested JR, and the answer was not black or white like we had hoped, but rather shades of gray.

So, we've been sitting, waiting, trying to muster the strength to figure this out once and for all.  In the back of my mind, I swing between the worst and best case scenarios.  I remember my sweet, 18 month old, in the midst of hives, throat constriction, vomiting, and sheer terror.  On the other hand, I think of a 4 year old enjoying waffles, french toast, and scrambled eggs.  I hope for the best, but am terrified of the worst.  So we wait...  until finally this past week, we mustered up the courage to try egg.  By the way, we were advised that he will likely be ok, but to watch him closely.  Can you say, "shades of gray?!".  After looking up some of the scientific literature on egg allergy, I completely agree with this rather "gray" assessment.  It just goes to show that we have a long way to go in making allergy testing more certain in diagnosing a true allergy!  I guarantee the doctors advising patients much be just as frustrated as the sufferers! 

JR and I made chocolate cookies, and I threw an egg into the mix.  Just as an extra precaution, I smudged a little cookie dough on JR's face to see if there were any signs of allergy.  Fifteen minutes later, redness and a small hive appeared where the cookie dough had been.  Both JR and I were devastated:  JR because he had to wait for me to whip up another batch of cookies without the egg and me, because it appeared egg may not safe after all.
Redness and small hive where egg-containing
cookie dough was placed ~15 min before photo
This was in no means a controlled, scientific experiment that shows JR will react to egg if eaten, I realize this fact.  There are many possible explanations given the poor "experimental" parameters tested that day (e.g. no experimental control, raw egg instead of cooked egg, etc).  What it does tell me, however, is that blood tests are only prediction tools and not great ones at that.  It is safe to say, we will be talking with our allergist about another food challenge, which is the only way to confirm the allergy one way or the other.... sigh.

Stay tuned for an egg allergy fact sheet and another installment in the "Fifty Shades of Egg" saga.

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