What is the management plan for a patient with acute on chronic diverticulitis (inflammation of the digestive tract) with abscess and possible colovesical fistula (abnormal connection between the colon and bladder) and involvement of the vulvovaginal cuff (area where the vagina and vulva meet) without drainage from the vagina or bladder?

Management of Acute on Chronic Diverticulitis with Abscess and Possible Colovesical Fistula

Surgical intervention with resection of the diseased colon segment and primary anastomosis is the definitive treatment for diverticulitis complicated by colovesical fistula, even when there is no active drainage from the vagina or bladder.

Initial Assessment and Diagnosis

• Confirm the diagnosis with CT findings showing:

  • Diverticular inflammation
  • Presence of abscess
  • Possible communication between colon and bladder
  • Involvement of vulvovaginal cuff

• Evaluate for classic symptoms of colovesical fistula:

  • Pneumaturia (air in urine)
  • Fecaluria (fecal material in urine)
  • Recurrent urinary tract infections
  • Abdominal pain

Management Algorithm

Step 1: Determine Severity and Stabilize

• Assess for signs of sepsis or hemodynamic instability
• Start broad-spectrum antibiotics covering gram-negative and anaerobic organisms 1
• Ensure adequate fluid resuscitation

Step 2: Abscess Management

• For abscess <4-5 cm: Consider trial of antibiotic therapy alone 1
• For abscess ≥4-5 cm: Perform percutaneous drainage under CT guidance combined with antibiotics 1, 2
  • Monitor drainage output
  • Remove drain when output ceases or decreases substantially
  • Consider CT with contrast via catheter before removal

Step 3: Definitive Management of Colovesical Fistula

• Even without active drainage, the presence of a colovesical fistula on imaging requires surgical intervention 3, 4
• The recommended surgical approach is:
  • Resection of the diseased colon segment with primary anastomosis 3, 4
  • Repair of bladder defect (simple closure)
  • Placement of omental flap between bowel anastomosis and bladder 4

Step 4: Timing of Surgery

• If patient is stable with controlled infection:
  • Complete a course of antibiotics (typically 4 days after adequate source control) 1, 2
  • Schedule elective surgery after inflammation subsides
• If patient shows signs of deterioration:
  • Proceed with urgent surgical intervention

Special Considerations

• Diverticular abscesses represent complicated diverticulitis with high risk of recurrence (60.5%) and disease complications 5
• Successful percutaneous drainage of abscess does not lower the risk of future recurrence or complications 5
• Colovesical fistula is the most common type (65%) of fistula associated with diverticular disease 3
• One-stage resection with primary anastomosis is safe and effective in 90% of patients 3
• Diverting colostomy or Hartmann procedure is generally not recommended for colovesical fistula as it doesn't provide definitive resolution 3

Post-Treatment Follow-up

• Follow-up colonoscopy 4-6 weeks after resolution to exclude underlying malignancy 2
• Monitor for recurrence of symptoms
• Advise on high-fiber diet to reduce risk of recurrent diverticulitis 1

Common Pitfalls to Avoid

• Failure to recognize deterioration in patients initially managed conservatively 2
• Inadequate drainage of large abscesses leading to treatment failure 2
• Missing underlying malignancy by not performing colonoscopy after resolution 2
• Prolonged antibiotic therapy beyond 4 days after adequate source control 2
• Underestimating the high recurrence rate (60.5%) after medical management of diverticular abscess 5

Remember that while initial conservative management may temporarily control symptoms, definitive surgical management is typically required for diverticulitis complicated by colovesical fistula to prevent recurrence and further complications.