What is anal fistula

Learn about our expanded patient care options for your health care needs. Most anal fistulas form in reaction to an anal gland that has developed a pus-filled infection abscess. Even if your abscess drains on its own, you have about the same risk for a fistula. Certain conditions that affect your lower digestive tract or anal area may also increase your risk.

An anal abscess is an infected cavity filled with pus found near the anus or rectum. Ninety percent of abscesses are the result of an acute infection in the internal glands of the anus. Occasionally, bacteria, fecal material or foreign matter can clog an anal gland and tunnel into the tissue around the anus or rectum, where it may then collect in a cavity called an abscess. An anal fistula also commonly called fistula-in-ano is frequently the result of a previous or current anal abscess. Normal anatomy includes small glands just inside the anus. The fistula is the tunnel that forms under the skin and connects the clogged infected glands to an abscess.

Last updated: May 18, Revisions: The majority are associated with anorectal abscess formation, with one third of patients with an anorectal abscess having an associated perianal fistula at the time of presentation. Anal fistulae usually present with either 1 recurrent perianal abcesses 2 intermittent or continuous discharge onto the perineum , including mucus, blood, pus, or faeces. Figure 1 — The Goodsall rule, used clinically to predict the course of a fistula tract. Proctoscopy can be used to visualise the opening of the tract in the anal canal.

Back to Anal fistula. There are several different procedures. In many cases, it's not necessary to stay in hospital overnight afterwards. The most common type of surgery for anal fistulas is a fistulotomy. In cases where the risk of incontinence is considered too high, another procedure may be recommended instead.