How is Perianal Crohn's Disease Treated?

Treatment of perianal Crohn's disease should be tailored to the symptoms of the individual. Thus, it's really important that your evaluation includes clinical history and examination; assessment of intestinal disease; and assessment of perianal disease.

In order of priority, the phases of treatment for perianal Crohn's disease are:

1. Drainage of infection to eradicate perianal sepsis
2. Stabilization and establishment on immunomodulator
3. Improvement of quality of life

Conservative Treatment of Perianal Crohn's Disease

In patients with Crohn's disease who have skin tags, hemorrhoids, and/or fissures, conservative management is advised because of the post-operative risk of poor wound healing, anorectal stenosis and the potential need for subsequent proctectomy (removal of the rectum). Methods employed include local measures (e.g., sitz baths, topical steroids, local Xylocaine) and stool modulating agents.

Hemorrhoids are uncommon in Crohn's disease. The most important aspect of the treatment of “hemorrhoids” in patients with Crohn's disease is the differentiation of hemorrhoids from anal skin tags.

Anal fissures tend to be painless and eighty percent heal with conservative treatment.

Surgery for skin tags, hemorrhoids and asymptomatic fissures rarely achieves healing and is frequently associated with complications. Thus, the principle of “do no harm” should be remembered; skin tags, hemorrhoids and asymptomatic fissures should be left alone.

Drugs for Perianal Crohn's Disease

Several drugs are used for the treatment of perianal fistulas in Crohn's disease.

Antibiotics such as metronidazole and ciprofloxacin have been used on the basis that bacterial flora contribute to perianal disease; however, the disease tends to recur once the antibiotics are discontinued.

Cyclosporin results in an 80% response rate but the benefits are often temporary and side-effects may include hypertension, renal failure and secondary infections.

Infliximab, an antibody that blocks the action of TNF-α, a harmful inflammatory cytokine produced by macrophages in the intestine, has been shown in two clinical trials to be effective in promoting the closure of fistulas. There is also some evidence that there is a better response rate and longer time to recurrence when infliximab treatment is preceded by seton placement.

Steroids are commonly used in the treatment of Crohn's disease but there is less evidence to suggest a benefit in perianal disease. In fact, steroids may prevent the healing of fistulas and lead to abscess formation.

Patients with perianal Crohn's disease are resistant to steroids. Topical aminosalicylates, given as enemas, may provide a targeted treatment.i

Surgical Procedures for Perianal Crohn's Disease

Treatment of a fistula aims to stop it from recurring and depends on where the fistula lies.

Seton: High anal fistulas are treated with draining setons usually in combination with infliximab therapy and immunosuppressives. A seton is a length of suture material looped through the fistula which keeps it open and allows pus to drain out. A seton can be left in place long-term to prevent problems. This is the safest option, although it does not cure the fistula.

Fistulotomy: The procedure to correct a low anal fistula is called a fistulotomy, an operation to cut the fistula open. In a fistulotomy the doctor cuts open the infected area which allows the fistula to heal. Sutures usually aren't used. This option leaves behind a scar, and depending on the position of the fistula in relation to the sphincter muscle, can cause problems with incontinence.

Fibrin glue injection: This involves injecting the fistula with biodegradable glue which should close the fistula from the inside out, and let it heal naturally.

This method is best tried before all others since, if successful, it avoids the risk of incontinence, and creates minimal stress for the patient.

Fistula plug: This is an advanced version of the fibrin glue method and involves plugging the fistula with a “plug” made of pig's gut. According to some reports, the success rate with this method is as high as 80%.

Fecal Diversion: The treatment of perianal disease frequently entails stool diversion by creation of a loop ileostomy to improve symptoms and manage infectious complications. Diversion using a colostomy is discouraged because Crohn's disease may involve the stoma and thus complicate its management.

Approximately fifty percent of patients with symptomatic perianal Crohn's disease will require permanent fecal diversion.ii There are no known predictors of which individuals will fail sphincter-sparing therapy and ultimately require fecal diversion.

Fecal diversion is easy for the patient to maintain and for the surgeon to reverse. There is an initial high rate of perianal healing in fecal diversion. However, for those patients with rectal or colonic Crohn's disease, recurrence of perianal symptoms is common and will eventually necessitate proctectomy, in other words, removal of the rectum.

Proctectomy: Patients with a young age of disease onset, with fistula as the first complication of perianal Crohn's disease, or with more than three perianal lesions have been identified as high risk for proctectomy. Fecal incontinence may be another indication for proctectomy.

The overall probability of proctectomy in patients with perianal Crohn's disease has been estimated to be 10 percent at 10 years, increasing by 1 percent each year.

Following proctectomy for Crohn's disease, non-healing of the perineal wound occurs commonly. Persistent pain can also be troublesome. Some patients report phantom sensations analogous to that following limb amputation. .

Treatment of perianal Crohn's disease remains a great challenge for clinicians. Patients must understand that while surgery will improve quality of life it does not provide a cure.

References for Perianal Crohn's Disease Treatment

Written by Dr. Kirchgessner, edited by Donald Urquhart