Thanks. VERY helpful. Thanks for the links to the IgA deficiency articles, too.

Can you tell me more about this? "It might not be a bad idea to test for IgG subclass deficiencies as well." Is that any relation to an ELISA test? I've heard of that.

Yes, I've thought about going GF w/ my daughter and I think we might if she only were gluten/casien free. But at this point she has so many digestive problems / sensitivities -- essentially on an SCD diet but even more limited than that -- that our whole family isn't yet prepared to join her in her diet. Getting some clear test results would help in that decision! Oh well.