What is the management approach for perianal conditions?

Management of Perianal Conditions

For perianal abscesses in Crohn's disease, perform adequate surgical drainage under general anesthesia without actively searching for an associated fistula, and if an obvious fistula exists, insert a loose draining seton rather than laying it open. 1

Emergency Management of Perianal Sepsis

Perianal Abscess

• Drain all perianal abscesses surgically under general anesthesia without routine wound packing 1
• Do not actively probe or search for an associated anal fistula at the initial abscess presentation 1
• If an obvious fistula exists without probing, do not lay it open—instead insert a loose draining seton 1
• Assess the rectum at the time of abscess drainage to evaluate for signs of proctitis, as this significantly affects prognosis and treatment decisions 1, 2
• No additional surgical fistula treatment modalities should be performed in the emergency setting 1

Perianal Fistula Management

Initial Diagnostic Approach

• Obtain contrast-enhanced pelvic MRI as the initial imaging procedure to assess fistula anatomy 2
• Perform proctosigmoidoscopy routinely during initial evaluation to assess for concomitant rectosigmoid inflammation 2
• Examination under anesthesia (EUA) by an experienced surgeon is the gold standard for definitive diagnosis and classification 2

Simple Perianal Fistulas (Low Intersphincteric or Trans-sphincteric with Single External Opening)

• Start with metronidazole 400 mg three times daily and/or ciprofloxacin 500 mg twice daily as first-line medical treatment 1, 2, 3
• Combine antibiotics with seton placement for symptomatic simple fistulas 2
• For patients without macroscopic rectal inflammation, consider fistulotomy (1- or 2-stage) which has the highest success rate 1, 3
• If antibiotics fail, use thiopurines (azathioprine 1.5-2.5 mg/kg/day or mercaptopurine 0.75-1.5 mg/kg/day) as second-line therapy 1, 2, 3
• Reserve anti-TNF agents (infliximab) for third-line treatment 3

Complex Perianal Fistulas (High Intersphincteric, High Trans-sphincteric, Extrasphincteric, or Suprasphincteric)

• Perform imaging before surgical drainage, then proceed with EUA for abscess drainage and loose seton placement 2
• Use anti-TNF therapy (preferably infliximab) combined with immunomodulators as first-line medical treatment after surgical drainage and seton placement 2, 3
• Add adjunctive antibiotics (metronidazole and ciprofloxacin) 3
• For patients with active rectosigmoid inflammation, use noncutting setons as the treatment of choice to maintain drainage and reduce abscess risk 1
• For patients without macroscopic rectal inflammation, consider endorectal advancement flap as an alternative to setons 1

Important Surgical Considerations

• Avoid fistulotomy in patients with active proctocolitis due to lower healing rates and higher incontinence risk 1
• Success rates for advancement flaps range from 50-100% when performed in the absence of active rectosigmoid inflammation 1
• Video-assisted anal fistula treatment (VAAFT) combined with advancement flap shows 82% success rate at 9 months 3
• Ligation of intersphincteric fistula tract (LIFT) procedure is an option for complex fistulas 3

Specific Perianal Conditions

Anal Fissures in Crohn's Disease

• Manage conservatively as fissures are usually painless and spontaneously heal in >80% of patients 1
• Reserve lateral sphincterotomy only for patients who fail conservative management 1

Hemorrhoids in Crohn's Disease

• Avoid simple hemorrhoidectomy, newer procedures for prolapsing hemorrhoids, or banding due to frequent postoperative complications including poor wound healing, anorectal stenosis, and high proctectomy rates 1

Anorectal Strictures

• Asymptomatic strictures do not require treatment 1
• Treat symptomatic patients with dilation; repeat dilations are often required 1

Rectovaginal Fistulas

• Only attempt surgical treatment in the absence of active rectosigmoid inflammation 1
• Never use fistulotomy for low rectovaginal fistulas due to sphincter injury risk 1
• Consider primary closure, transanal advancement flap, sleeve advancement flap, or transvaginal advancement flap 1
• Success rates range from 50-100% 1

Monitoring Treatment Response

• Clinical assessment (decreased drainage) is usually sufficient to evaluate response 2
• Use MRI or anal endosonography combined with clinical assessment to evaluate improvement of fistula tract inflammation 2
• Critical caveat: Clinical closure does not equal MRI closure—there is high risk of recurrence without complete fibrotic tract on MRI 2, 3

Refractory Disease Management

• Consider hyperbaric oxygen therapy and fecal diversion for refractory cases 3
• Avoid temporary diverting ileostomy or colostomy as most patients never have intestinal continuity restored 1
• Reserve proctectomy as a last resort for severe disease with irreversible perineal destruction (historically 10-18% of conservatively managed patients) 1, 3

Key Pitfalls to Avoid

• Never excise skin tags in Crohn's disease 1
• Do not perform aggressive surgical procedures in the presence of active proctitis 1, 2
• Avoid immunosuppressive therapy before draining abscesses 4
• Monitor for malignancy development in chronic perianal fistula tracts 1, 3