Just a thought about coeliac testing - you can get false negatives on the standard coeliac blood tests if you are IGA deficient -there is some recommendation somewhere that if coeliac is suspected and the usual blood tests are neg, then need to check total IGA levels to make sure that isn't giving a false negative. I wonder if this might explain some of the gluten sensitive, but not diagnosed coeliac people. Unfortunately negative biopsies aren't a good way to say "definitely not coeliac" (though a positive one definitely confirms it) - just because coeliac damage can be incredibly patchy and start much lower down than standard endoscopies go.
