Because Crohn’s disease cannot be cured by surgery, the guiding surgical principle is to do as little as possible while relieving symptoms as completely as possible. Risks of iatrogenic injury combined with disappointing surgical results prompt a conservative approach in nearly all patients. We agree completely with Alexander-Williams’ observation that “fecal incontinence is the result of aggressive surgeons and not progressive disease.”
Although some perianal lesions heal spontaneously without specific treatment, surgery has an important role. Anorectal surgery in inflammatory bowel disease is primarily a management tool for complications. The goal of operative intervention is preservation of sphincter function along with elimination of perianal symptoms.
Which patient deserves operative intervention? First, perianal pathology must be symptomatic. Many Crohn’s disease patients will have what has been coined as a “dry fistula.” These asymptomatic patients have no current complaints, and therefore, no treatment is warranted or prudent. Second, all perianal sepsis must be drained or controlled. Third, rectal disease must be absent or in a state of quiescence. Fourth, the diagnosis must be secured. As previously discussed, the use of MRI or EUS and examination under anesthesia increases the accuracy of our diagnostic skills. Once the diagnosis has been made, the proper surgical intervention can be undertaken. There is also a separate chapter on anorectal disease with and without inflammatory bowel disease.
Is it prudent to perform a hemorrhoidectomy in a Crohn’s disease patient? In the past, complications such as fistula, stricture, abscesses, and need for proctectomy precluded hemorrhoidectomy in patients with Crohn’s disease. In contrast, Wolkomir reported successful outcomes in healing in 15 of 17 patients undergoing hemorrhoidectomy. Nonetheless, hemorrhoids generally are not removed in patients with Crohn’s disease, because of potential imperfect wound healing and stricture formation. There is a separate chapter on hemorrhoids.
Fissures in Crohn’s disease typically appear in positions other than anterior and posterior. But, like non-inflammatory bowel disease fissures, most heal spontaneously and require no surgical therapy. Some fissures in perianal Crohn’s disease are asymptomatic whereas others cause significant discomfort. In general, fissures in Crohn’s disease are managed conservatively. For those who fail conservative management, surgical intervention is indicated. Wolkomir and Luchtefeld (1993) treated 25 patients with symptomatic fissures surgically and complete healing occurred in 22. Fleshner and colleagues (1995) compared medical with internal sphincterotomy for fissures in Crohn’s disease patients. They found healing in only 49% of those treated medically, but 88% of fissures healed in those undergoing surgery.
Anorectal strictures are commonly found on digital rectal examination in patients with perianal Crohn’s disease. Most patients with mild stenosis are asymptomatic. When the degree of stenosis becomes severe enough to cause difficulty with evacuation, most patients respond to simple finger dilatation. In 1986, Bernard and colleagues reported on seven patients with anal stenosis. Patients eventually responded to anal dilation. The historical four-finger dilatation should, of course, be avoided in patients because risk of incontinence is prohibitive.
Although short, mild strictures respond to gentle dilatation, long strictures in general do not. Patients with these more problematic strictures have a very high likelihood of coming to proctectomy. Keighley and Allen in 1986 and Linares and colleagues in 1988 documented that up to 86% of their patients with severe stenosis had to be diverted.
When a patient with inflammatory bowel disease presents with perianal pain, perianal sepsis is the most common cause. In turn, the two most common causes of perianal abscess are cryptoglandular infection or an obstructed fistula tract. The treatment of perianal abscess includes prompt and adequate surgical drainage. The location of the abscess will determine the surgical approach. For superficial abscesses, simple incision and drainage is effective in the majority of cases. Abscesses which are deep to the sphincter mechanism (supralevator or ischiorectal) should be drained using a mushroom catheter and/or a noncutting Seton to provide adequate and continued drainage with as little tissue disruption as possible.