I dug up an old healingwell post entitled large red blood cells from uc forum:
www.healingwell.com/community/default.aspx?f=38&m=1047193malka said...
I went to the hematologist today and his opinion was that the most likely cause of the large red blood cells was the azathioprine (Imuran). He said that it was not harmful and there was no need to do anything. The only reason to investigate is that large red blood cells can be a symptom of various other things - none of which seemed likely in my case. He could tell definitively if I stopped taking my medication for six weeks and be retested, or through a blood marrow test. Unless things changed, however, he saw no need to do any of that. (We agreed that it was not worth the risk of a flare.)
I guess it was much ado about nothing. When I told my GI about it, he said it was probably the result of medication, but that I should go to the hematologist anyway.
So - that's the news from Lake Wobegon . . . .
M