Can my father have a colonoscopy if he has an anal fissure?

My Dad has been diagnosed with an anal fissure. He has diarrhea that consists mostly of blood and mucous about 30 times a day. It is very painful. He has pain across his entire abdomen before a bowel movement. He has lost 30 pounds in the last 4 weeks because he has a difficult time eating and drinking because of the abdominal pain that follows. We have a family history of ulcerative colitis but he had a colonoscopy last year (when symptoms were not present) and a biopsy and they found it was not ulcerative colitis. The doctor is saying that surgery for an anal fissure should make this better and that they cannot do a colonoscopy because of the anal fissure. In your opinion, should he have another colonoscopy and can an anal fissure alone cause this type of suffering?

Healthcare Providers (1)

Anal fissures can cause this much pain, but not usually diarrhea. colonoscopy can be very painful if he has an active anal fissure. But it should be considered if he has this much diarrhea and weight loss.

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