True enough, but if the hypothesis is correct, maybe they all have the same etiology. We like to separate immunology from neurology, but the two disciplines are probably more involved with each other than we realize, especially in the gut, IMHO.
From what I’ve read, IBS is directly related to mood disorders, specifically depression. In other words, it’s something to do with neurochemicals, not the digestive tract.
While trying not to be gross, I will say that I suffered from horrible IBS for years. Once my depression was diagnosed and I began drug therapy, the IBS vanished.
To my knowledge, I have never had worms of any kind...