I have been experiencing dehabilitating instances of vomiting, low pulse

Patient: I have been experiencing dehabilitating instances of vomiting, low pulse and abdominal pain for over 8 yrs. I get admitted to the hospital, stabalize within 3-6 days, they find little to nothing( low potasium and dehydration) then I am released. This has occured 12 times, they haven’t found anything with diagnostic equipment. Over the past two year I began having blood in my stools, abdomen pain and diarrhea. My rectum and now hip, on top of the abdomen pain, abnormal stools and vomiting 2-3 times a week, has just been getting worse.Recently I had a CT with contrast which showed some diverticula then an MRI showing bowel wall thickening. Can you tell me why these to would show something different? I have no idea what they are checking for, I am awaiting my second colonoscopy.

Doctor: