Pediatric Fistula-in-Ano Treatment & Management

Medical therapy includes antibiotics and analgesics. In addition, treatment of the cause (eg, malignancy, Crohn disease, ulcerative colitis) is necessary. If underlying tuberculosis is detected, antitubercular treatment using rifampicin, isoniazid (Isonex), and ethambutol should be administered for 6 months.

Asymptomatic fistulae require no treatment. Submucosal, intersphincteric, or low transsphincteric fistulae may be adequately treated using fistulectomy or fistulotomy. Treatment varies according to the patient's sex and according to the type of fistula.

Fistulectomy

With the patient under anesthesia, the fistula tract is dissected from all sides by means of sharp dissection with scissors or diathermy from the external opening to the internal opening. The cavity left behind is allowed to heal by secondary intention.

Fistulotomy

With the patient under anesthesia, the fistula tract is probed. The probe is passed from the external opening and taken out from the internal opening. The whole fistula tract is then laid open over the probe. As with fistulectomy, the wound is allowed to heal by secondary intention.

Radiowave fistulotomy

Radiowave fistulotomy offers benefits such as less postoperative pain, faster wound healing, and an early return to normal activity.^[3] However, recurrence rates and continence problems are similar to those following conventional techniques.

Treatment of high anal fistula

A supralevator (pelvirectal) fistula may be secondary to local disease. If a traumatic fistula perforates the rectal ampulla, colostomy is usually needed.

Treatment of transsphincteric fistula

A transsphincteric fistula usually starts as an intersphincteric tract with a secondary tract in the ischiorectal fossa extending up to the levator axis. Treatment is directed toward the lower part of the tract, as healing of the upper tract may occur. If this does not take place, colostomy is required.

Treatment of intersphincteric high anal fistula

This primarily starts as an abscess of the anal gland and extends upward and downward between the internal and external sphincters. Patients may have an opening into rectum above the anorectal ring. Treatment consists of laying open the tract by dividing only a small segment of the internal sphincter.

Use of seton, including medicated seton (Kshara sutra)

A seton is a surgical thread often used to treat this condition. The seton can be silk, cotton, or any other suture material. It may be coated with medications. A Kshara sutra is a medicated thread often used in India to treat fistula-in-ano.^[4] To prepare this medicated type of seton, equal amounts of milk from the Euphorbia neri-folic plant and powder of dry rhizomes from the plant Carcuma longa are thoroughly mixed. Cotton surgical threads (No. 20) are immersed in the mixture for 1-2 hours and then dried in hot air. This procedure is repeated often, sometimes as many as 7 times.

Medicated setons are not commonly used in rest of the world. Medications used in the Kshara sutra are anti-infective and anti-inflammatory.

With the patient under anesthesia, the fistulous tract is probed to determine its extent and direction. A silver malleable probe is passed into fistula tract, and a suitable length of seton (Kshara sutra) is cut and threaded over the eye of the probe. The Kshara sutra is moderately tightened and is tied outside the anal verge over a piece of gauze.

A new piece of Kshara sutra is replaced and tied every 6 days, using the railroad technique, until the last seton cuts through the fistula tract. The thread is shortened during each change, and the tract shortens. The wound heals by secondary intention.

The fistulous tract is cut as a result of the pressure the Kshara sutra exerts on the anorectal tissue. The presence of the Kshara sutra does not allow the cavity to close and facilitates continuous drainage of pus. Cutting and healing of the tract occurs simultaneously, and no pus pocket is retained. Chemicals applied on thread are anti-inflammatory agents and have antibacterial properties. In addition, the alkaline pH of the Kshara sutra prevents rectal pathogens from invading the cavity.

About 95% of patients are completely cured, and 5% have a recurrence. Subsequent application of a Kshara sutra is painless in 85% patients.

Follow-up care involves antibiotic treatment, surgical dressing, and use of laxatives. A high-fiber diet is recommended.

Complications of fistula-in-ano include recurrence, delayed and/or impaired healing, anal disease, mucosal prolapse (which is not uncommon after fistula surgery), and incontinence.

Outcome is good for the acquired and congenital varieties. Recurrence and scarring are common in patients with tuberculosis or Crohn disease.

In a retrospective study of fistula-in-ano in children, Novotny et al (2008) demonstrated that recurrence is more likely in older children and in children who had previous episodes of perianal abscess or if pus was noted at the time of surgery.^[5]