What is the treatment for feces coming out of the vagina, possibly due to a rectovaginal fistula?

Treatment of Rectovaginal Fistula

The first critical step is to determine whether the fistula is malignant or benign, as this fundamentally changes management: malignant fistulas require oncologic resection (never local repair), while benign fistulas can be managed with medical therapy initially or surgical repair depending on etiology and complexity. 1

Immediate Diagnostic Priority: Rule Out Malignancy

• Always exclude malignant etiology before initiating any treatment, as anti-TNF agents and local repair procedures are contraindicated in malignant fistulas and will delay definitive oncologic care 1, 2
• If malignancy is confirmed, proceed directly to oncologic resection with curative intent when possible, or fecal diversion for palliation if resection is not feasible 1

Management Algorithm for Benign Rectovaginal Fistulas

Step 1: Assess Fistula Characteristics

Determine the following factors that guide treatment selection 3:

• Size and location (low/anovaginal vs. high rectovaginal)
• Etiology (obstetric, inflammatory bowel disease, radiation, iatrogenic)
• Complexity (simple vs. complex based on size >2.5cm, high location, radiation/IBD etiology, or recurrent)
• Presence of active inflammation or infection
• Status of anal sphincter complex
• Previous repair attempts

Step 2: Initial Medical Management (When Appropriate)

For inflammatory bowel disease-related fistulas:

• Initiate anti-TNF therapy (infliximab) with induction dosing at weeks 0,2, and 6, followed by maintenance every 8 weeks 2
• Co-administer immunosuppressants (azatioprine, 6-mercaptopurina, or methotrexate) from the start to prevent immunogenicity and maintain remission 2
• Rule out and drain any associated abscesses before starting infliximab 2
• Continue maintenance therapy even after clinical closure to prevent recurrence 2

For small, minimally symptomatic fistulas:

• Conservative management may be effective and should be attempted for 3-6 months 3
• This approach is reasonable for obstetric fistulas with minimal symptoms 3

Step 3: Surgical Intervention

Indications for surgery include:

• Failure of medical therapy after appropriate trial 2, 3
• Large or complex fistulas with severe symptoms 3
• Obstetric fistulas (typically amenable to local repair) 4
• Recurrent infections or abscess formation 2
• Patient preference for definitive treatment 3

Surgical approach selection:

• Simple, low fistulas: Local transanal or transvaginal advancement flaps 3, 5
• Complex or recurrent fistulas: Interposition of healthy, well-vascularized tissue (Martius flap, gracilis flap) 3, 6
• High rectovaginal fistulas: May require transabdominal approach 3
• Associated sphincter damage: Concurrent sphincteroplasty with fistula repair 3, 4

Timing considerations:

• Control active inflammation before surgical repair 2
• Achieve endoscopic mucosal healing in IBD-related fistulas before attempting repair 2
• Consider initial diverting stoma for severe symptoms or large fistulas to provide symptom relief before definitive repair 3

Step 4: Special Circumstances

Radiation-induced fistulas:

• Exclude cancer recurrence first 4
• If patient is not a candidate for radical resection, perform fecal diversion alone 4
• Local repair has high failure rates due to poor tissue quality 4

Crohn's disease with severe rectal involvement:

• Proctectomy is usually required if rectum is severely diseased 4
• Local repair only considered if rectum is relatively healthy and sepsis controlled 4

Critical Pitfalls to Avoid

• Never attempt local repair procedures (advancement flaps, sphincteroplasty) for malignant fistulas - these are contraindicated and will fail 1, 2
• Do not start infliximab without first ruling out and draining associated abscesses 2
• Do not discontinue immunosuppressants after achieving closure with infliximab - maintenance therapy is essential 2
• Do not assume clinical closure equals complete healing - high recurrence risk exists without complete tract fibrosis 2
• Avoid operating on actively inflamed tissue in IBD patients - wait for mucosal healing 2