Hello, Fellow Travelers:

I am sorry to throw a monkey wrench into things, but have you heard of "microscopic colitis" (MC)? I was told ever since childhood that I had IBS and there was nothing my mother could do to help me. When FODMAP diet came along, I went through two courses of evaluation 2 years apart without relief. And I was very diligent with no backsliding. A SIBO test was negative. Then I was finally had a scoping that wasn't negative. Biopsies were taken at the right spots and voila! Microscopic Colitis. Meds didn't work to control it, so I am now on IV Entyvio. Fingers, toes, and eyes all crossed!

I know that it sounds patronizing, but MC really IS a thing. This form of colitis is not seen via a scope during endoscopies - the GI tract looks normal. It is only when biopsies land on the right places that a pathologist can make the diagnosis under a microscope (hence, the name).

* I recently read an article in a European journal called "Maedica: A Journal of Clinical Medicine" about the similarity of IBS-Diarrhea symptoms compared to MC. The article is titled: "Microscopic Colitis – A Missed Diagnosis in Diarrhea-Predominant Irritable Bowel Syndrome". It is a plea for intractable cases of IBS-D to be scoped and examined for MC.

From the article - - -
"Conclusions: All the patients thought to have diarrhea-irritable bowel syndrome should be evaluated for microscopic colitis. Symptomatology is almost superimposable, but a few distinct features can
be noticed. The proper and early diagnosis and the specific treatment may lead to significant clinical
improvement in some difficult cases of the so-called “irritable bowel syndrome”." Volume 7 No.1 2012.

* "Microscopic Colitis" - https://www.mayoclinic.org/diseases-conditions/microscopic-colitis/symptoms-causes/syc-20351478

This may not be your problem, but it might be for some people. All the best!