What my GI explained to me when he DX me on top of CD (which I had already had for 12yrs at that time) with IBS as well was, it was not uncommon for IBDers to also end up developing IBS especially those IBDers who have frequent and/or long term flares from their IBD, that IBS was more then reasonable to factor in as well since afterall, for those who have prolonged IBD flares and/or frequent IBD flares, it stands to reason that you're at a high risk of also developing an irritable bowel as well...with him being a top lead researcher for crohn's and colitis in Canada I feel confident in his reasoning even though many GI's would disagree with him, they may very well not be as experianced (or even
open-minded enough) as him.
And yes, it's been long confirmed that they are 2 totally seperate entities, which is another reason why it's not impossible to have both conditions, it's like saying a person cannot have both MS and cancer, just because IBS and IBD have some similarities does not mean they cannot coincide together...my veiw of having both IBD and IBS as my GI believes I do is, same crap, different pile...BTW, at the same time he DX as also having IBS along with crohn's, he tested me for lactose intolerance of which the results came back positive...and I was severely lactose intolerant (thank gawd for the probiotics I take which has cleared that issue up for me) but just goes to show, one person (or thousands) can have IBD, IBS and lactose intolerance all at the same time.
My bum is broken....there's a big crack down the middle of it! LOL :)