To diagnose anal fistula, your doctor will ask about your symptoms and examine you. He/She may also ask about your medical history. Your doctor will usually refer you to a specialist colorectal surgeon (who specializes in conditions that affect the bowel). Your surgeon will examine your anus and rectum to diagnose an anal fistula. He/She may do a digital rectal examination (DRE) to examine the area. In this examination your surgeon will insert a lubricated gloved finger into your rectum and feel the texture of the skin.
Attribution: BUPA