I have run across a couple of people who sufferred for years, when finally they ran into a doctor who did both... and in both of those cases it ended up that they had damage higher up, where the damage isn't supposed to be. Those two people also healed with a gf diet, so there wasn't any mistake.

I'm pretty sure I've seen an abstract or two stating that it is a possibility that should be covered... I'll see if I can dig, at least one of them up.