Just thought I'd write to tell you that you are very much not alone with your bowel and bladder issues! The bladder thing I have been told is autonomic - I feel as though I'm doing all the 'normal' things, but it's as though the message for the bladder to 'open' just doesn't get through for ages, so as you describe, I just sit for ages and wait!
Prof. Aziz - I can't help much with the procedure for his NHS patients, but for his private patients he sees them for 45 mins to an hour initially in the outpatient department and then the tests are arranged after that. We have some patients who come from very far away (think Qatar, Ireland, America...) and they are often admitted for a few days so that all the testing can be done in one visit. Prof. Aziz also often has telephone appointments with his patients after he's seen them the first time, as sometimes that's easier for the patients, particularly those with mobility problems, or who live far away. Prof. Aziz works closely with Prof. Grahame and Prof. M. (autonomic specialist), and also with specialist GI nurses (they use the Peristeen system quite a lot) and dieticians. A lot of his patients seem to try the FODMAPs diet, and some report getting a lot of success from it. It might be worth looking it up, or asking a local dietician about it while you're waiting for your referral. I think that it looks a bit scary (it's certainly very restrictive), but if your diet is very restricted anyway, it might be worth giving it a try.
Hang in there - I know that a lot of Professor Aziz's patients have almost lost hope by the time they meet him, but there really are things that can be done!
29 years old, diagnosed with EDS-H at UCH in 2009. Severe brittle asthma since childhood.