I only know one person that has ichthyosis (LI) and intestinal issues, but I think hers is more age related than ichthyosis related because it is diverticulosis plus some food sensitivities to corn and pork.
I suppose it is possible that they are linked, but I'd be looking at straight food allergies or celiac disease or other more mundane things first, which you are already doing.
Whatever it is, I hope it clears up quickly!
Ichthyosis-en-Confetti Type 2
Husband, Nathan - 10, Elliot - 7, Oliver - 4, all affected.
I also have an unaffected daughter, age 8.
email: jennifer at confettiskin dot com
facebook - find me on "ichthyosis mommy spot" or "friends of ichthyosis"