Have any of you had a colonoscopy and been told you have "melanosis coli" - a darker pigmentation in the walls of your colon?  I had a colonoscopy 5 years ago & they found this, but said my colon was otherwise normal.  Of course, this was before the mast cell question arose, so no biopsies were taken.  (The doctor asked me if I took a lot of laxatives, which I never have.  The only explanation on that line was that in the early 2000s, I was into eating Atkins candy bars & they have sugar alcohol in them.  It is apparently indigestible.  It caused me a lot of GI discomfort, so I began avoiding products containing it.)  I now wonder if this is a symptom of MCAD?

Thanks, Ana - good to get confirmation that it is considered benign!  I expect I'll be having another one in the near future, provided I can be adequately pre-medicated.  I also have a hemangioma on my liver.  I wonder if it is actually a collection of mast cells