Thank you for the update @Rejoicephd it is good to know that you may have some answers.  Keep up the good work with your diet, and do let us know if you do get a firm diagnosis.  I took so long to feel better and for my TTG levels to normalise,  but got there in the end, so also bear in mind it does take longer for some of us.

Well, three months later and a startling revelation!  After going gluten free (and nearly bankrupt buying special foods), my wife made a lunch of meat potatoes and gravy made with Bertolli white sauce - no wheat there right?  Big flare up withing hours and I was really wiped out with it.  She rechecks the label on the sauce bottle and right at the bottom of the ingredients XANTHAN GUM. There's our #1 suspect again!  So by way of experimenting, she decided to try making a loaf of bread with just regular white flour like she used to do and see what happened; the familiar smell hit me when I walked in the door last night and I sat down to eat this still warm, fresh goodness - I thought even if I have to take Imodium sandwiches, it will be worth it 😋 No ill effects, either overnight or today!  Half the loaf is now gone because I had some for supper, saving just one last slice for breakfast in the morning` - I've used the bathroom once and that was normal, so maybe it is not the gluten after all? Can't wait to try a beer! 😁

Unfortunately, the development of celiac disease usually is not an end in and of itself. It usually brings along friends, given time. It is at heart an immune system dysfunction which often embraces other immune system dysfunctions as time goes on.

Thanks so much for the responses. I will urge him to go for further investigation. To be 48yrs old and develop a new allergy.. ugh, As if celiac disease isn’t enough! 

This does not seem to be an anaphylactic response but I agree it would be wise to seek allergy-food sensitivity testing. You might look into ALCAT food sensitivity testing.