What is the best course of action for a patient suspected of having an entero-uterine fistula due to air in the endometrial cavity?

Management of Suspected Entero-Uterine Fistula with Air in the Endometrial Cavity

For a patient with suspected entero-uterine fistula due to air in the endometrial cavity on CT, referral to Urogynecology is the most appropriate next step in management to ensure proper evaluation and multidisciplinary care.

Diagnostic Approach

Initial Evaluation

• CT finding of air in the endometrial cavity is suggestive but not specific for entero-uterine fistula
• Common symptoms to assess:
  • Passage of stool, gas, or odorous discharge from the vagina
  • Recurrent vaginal infections
  • Dyspareunia and perineal pain 1

Imaging Confirmation

1. Water-soluble contrast studies:

   • Water-soluble contrast enema is indicated for evaluating suspected fistulas and sinus tracts 1
   • Should be performed before barium studies due to risk of peritoneal contamination
   • Note: Limited sensitivity (33.3%) but good specificity (96.3%) for fistulas 1

2. Advanced imaging:

   • MRI with IV contrast: Superior for soft tissue delineation and visualization of collapsed tracts 1
   • CT with rectal contrast: Higher sensitivity (91%) and specificity (100%) than contrast enema alone 1
   • Consider combined approach (CT with water-soluble contrast) for improved diagnostic accuracy 1

Management Considerations

Multidisciplinary Approach

• Entero-uterine fistulas require joint management with medical control of inflammation and surgical intervention 2
• The British Society of Gastroenterology strongly recommends that enterovaginal fistulae should be managed jointly with medical and surgical teams 2

Surgical Management

• Most entero-uterine fistulas will require surgical intervention for definitive treatment
• Surgical options include:
  1. Resection of the affected bowel segment with primary anastomosis
  2. Hysterectomy may be necessary depending on the extent of uterine involvement
  3. Endoscopic approaches may be considered in select cases 3

Special Considerations

• Underlying etiology assessment is crucial:
  • Diverticulitis and neoplasias are common causes of fistulas 1
  • Inflammatory bowel disease may require specific medical management prior to surgery 2
  • Previous history of uterine artery embolization or intrauterine device use may be relevant 3, 4

Referral Pathway

When to Refer to Urogynecology

• Urogynecology referral is appropriate for:
  1. Suspected entero-uterine fistula based on imaging findings
  2. Complex fistulas requiring multidisciplinary management
  3. Cases where the exact origin of the fistula is unclear

When to Consider Additional Specialists

• Colorectal surgery consultation for bowel involvement
• Gastroenterology if inflammatory bowel disease is suspected
• Interventional radiology for potential drainage of associated collections

Follow-up Care

• After surgical repair, patients should undergo:
  1. Post-operative imaging to confirm fistula closure
  2. Regular follow-up to monitor for recurrence
  3. Assessment for underlying conditions that may predispose to fistula formation

Remember that entero-uterine fistulas are rare but serious conditions that significantly impact quality of life and require prompt, accurate diagnosis and treatment by specialists with experience in managing these complex cases.