I am 64 years old and have suffered increasing food intolerances for the last 7 years. It all seemed to start after taking Ciprofloxacin and developing a rectal yeast infection that lasted for over a year. Eggs were the first to go and then dairy. Both produced rapid explosive diarrhea and gas. My gall bladder was removed 3 years ago and then the diarrhea and digestive problems became overwhelming. I lost 50 pounds (that I couldn't afford to lose and began to wonder if I would even live to see my 65th birthday). The biopsy done just prior to the gall bladder surgery was negative for celiac disease. Eventually I did have the Enterolab testing done and antibodies to gluten were found in my stool test. Also I carry one of the main celiac genes. I started a gluten free diet but made many cross-contamination mistakes and also would give-up after 3 or 4 months and try toast, etc again. I wasn't seeing any improvement. Well, the good news is that in December of this year after really gluttening myself over the Christmas holidays I decided to go back on the diet and to stick to it religiously. And finally the improvements started to happen. I no longer have diarrhea, the constant bowel pain has lessened greatly and the variety of foods that I can tolerate has greatly improved. I have now gained 12 pounds and know without a 'shadow of a doubt' that I have done the right thing.
I did see an Internal Medicine specialist last month and she said that in her opinion "a positive response to the diet is much more important than any testing that doctors can do". She indicated that the tests have many false negatives. She thought that my age contributed to my slow response to the diet but she did say that she always tells her patients that if they want to try a gluten-free diet they must stick to it religiously for AT LEAST six months. She counsels them not to necessarily expect immediate improvements.
Just thought that you might find my experience helpful.