Great for Victoria. And good of the BBC to report on it, including what is needed to diagnose it. I can't remember the source or in what context, but I recently read a whole CBT/BPS thing on these symptoms, explaining how wanting to be near a toilet because of sudden upcoming diarrhea was anxiety that you needed to be trained out of. (The thought that you needed to be near a toilet was seen as a cognitive distortion of course.) Healthy people with zero experience of these conditions patronisingly "teaching" people who do have them how to train themselves out of it, I deeply detest this ableism pretending to be science.
This is a good example of why we need to study tissues more in ME. Everyone keeps looking at the blood and we never get anywhere. Studying gastric biopsies in ME patients with severe stomach symptoms, for example, would be a good idea. Nobody has done it yet.