How can you differentiate between endometriosis, which causes bleeding in the rectum and bladder, and other diseases of these two organs?

Evaluation: It is uncommon but certainly possible for endometriosis to invade deeply into the bladder or rectum. A cystoscopy of the bladder and a colonoscopy would be very useful to help figure that out.

Endometriosis: Via a colonoscopy and biopsies of suspicious areas and by doing cystoscopy and biopsies as well. Imaging studies like ct, mri, ultrasound can help with the initial evaluation in differentiating other pathologies.