What is Anal Fistula? An anal fistula is an abnormal connection or tunnel that forms between the anal canal (the end portion of the digestive tract) and the skin around the anus. It typically develops as a result of an infection or an abscess (a collection of pus) in the anal glands, which are small glands located near the anus. Anal fistulas can cause various symptoms, including ... https://surgikure.com/fistula-treatment/