Anorectal Fistula
An infection of the anal glands, fissure (tear) or abscess in the anus or rectum can sometimes cause drainage to create one or multiple tunnels (tracts) in the surrounding tissue. The tracts of these anorectal fistulas surface on the skin about the anus (or sometimes into the bladder or vagina), causing drainage, itching and pain. Over time, the fibrotic (hard) tracts become permanent and continue to drain pus and sometimes fecal material, increasing the risk of infection spreading about the anus and throughout the body. Anorectal fistulas are also common after radiation and with Crohn's disease and rectal cancer.
Medical Treatment
According to S.C. Smeltzer and B. Bare in Brunner & Suddarth's Textbook of Medical-Surgical Nursing, treatment varies according to the degree of infection and the cause of the fistulas. Initial treatment to reduce infection usually includes antibiotics and Sitz (warm) baths 3 to 4 times daily to increase circulation and reduce inflammation. Drainage may irritate the skin, so you should use a skin barrier cream/ointment (Aloe Vesta, Calmoseptine) and disposable pad. Fecal drainage can infect the vagina and/or bladder, so you must practice good hygiene, washing the area frequently and changing disposable pads when they are soiled.
Minor Surgery/Procedures
In some cases, surgical repair is not indicated, such as with Crohn's disease (because fistulas tend to recur), so treatment aims to prevent the fistula tracts from sealing over at the surface, causing the drainage to pool and form an abscess. If an abscess has already formed, the surgeon opens the tract and drains the abscess. Sometimes, the surgeon threads suture material (a Seton) through the fistula tract to keep it patent (open) and draining. The surgeon may also insert a small drain into the tract. According to Mayo Clinic, if the fistula is small and clean, the surgeon may choose to suture the inside of the tract and then seal the tract with surgical fibrin or collagen glue from the outside.
Surgical Treatment
According to HemorrhoidNet, about 20 percent of fistulas recur after surgery, but surgical removal is the only effective cure for most fistulas. Because the fistulas usually travel through the anal sphincter (the tight band of muscles that closes the anus), surgical repair can damage these muscles and cause fecal incontinence. Surgical procedures include fistulotomy, which excises (cuts away) the opening on the inside and the lining of the tract, and fistulectomy, which excises the entire tract. Sometimes a laser is used to remove the tract. According to Mayo Clinic, another approach is to cut a flap from the wall of the rectum to cover the area where the inside of the tract is removed. A Seton (length of suture or rubber band) may also be placed about part of the sphincter muscle so that it cuts through slowly, causing less damage than surgical excision.
