12/4

So, John is bright red all over (except his head) and by tonight the "rash" has become quite painful.  The PA and nurse practitioner think it is most likely graft v host disease but just to be sure, they did a skin biopsy.  In case you're wondering, that is a procedure where a topical anesthetic is injected to numb you to the third pencil size diameter tube of skin half an inch deep that is being drilled out of your arm.  Judging from the expression on John's face, it looked like it pinched more than a "little bit."  The  results of the skin biopsy can be ambiguous and unable to totally rule in gvhd or rule out a drug reaction.  Nonetheless, it was good to get checked out and to begin the treatment which is a massive dose of steroids to reduce the rash, pain and itchiness.  An additional upside of the steroids is their potential to increase John's appetite; a downside is their potential to make John a little physically manic and to interrupt sleep.  We see the dr on Thursday so we'll find out in a couple of days how the steroids are working.

What is going on here?  For the literati, it is the new immune system saying "Hello!  Here I am!"  For the scientists, antigen-presenting cells in the skin (and some other organs like the liver) are still showing John's proteins which the new immune system recognizes as foreign now hence the new immune system attacks John.  It's important to treat the gvhd early so it doesn't progress to a more advanced form that does more damage and is harder to treat.  Seems likely that John's problem has been caught in plenty of time; we and the medical staff are optimistic.

We're told gvhd is a very common complication of transplant.  Putting the best possible face on it, our nurses tell us it is a good sign that the new immune system is working :)