Fistula is an abnormal connection or passageway that forms between two organs, tissues, or vessels that do not normally connect. In the context of anorectal conditions, the most common type is anal fistula, which develops between the inner anal canal and the skin around the anus. It usually occurs as a result of infection in an anal gland, leading to the formation of an abscess. When the abscess drains or bursts, a tunnel may remain, forming a fistula.

Anal fistulas can cause significant discomfort and often do not heal on their own. Common symptoms include persistent pain around the anus, swelling, redness, discharge of pus or blood, foul smell, skin irritation, and difficulty in sitting. Some individuals may also experience fever or repeated infections due to the continuous drainage from the fistula tract.

Several factors increase the risk of developing a fistula. These include untreated anal abscesses, inflammatory bowel diseases like Crohn’s disease, trauma, tuberculosis, radiation therapy, and infections. Poor hygiene and chronic constipation may also contribute. In rare cases, fistulas can form in women after childbirth due to injury to the tissues.

Diagnosis is usually made through physical examination. In complex cases, doctors may advise MRI, ultrasound, or sigmoidoscopy to determine the depth and direction of the fistula tract. Identifying the exact pathway is essential for appropriate treatment.

Treatment of fistula almost always requires a medical or surgical procedure, as simple medications cannot close the tract. Common treatments include fistulotomy, where the tract is opened and allowed to heal naturally; seton placement, which helps drain infection and gradually cuts the fistula; laser therapy; and advancement flap surgery, used for complex fistulas while preserving sphincter function. Modern, minimally invasive techniques such as VAAFT (Video-Assisted Anal Fistula Treatment) and LIFT (Ligation of Intersphincteric Fistula Tract) offer faster recovery and minimal pain.