Colovesical Fistula Diagnosis and Management

Clinical Presentation

• The American College of Radiology notes that pneumaturia and fecaluria are pathognomonic findings for colovesical fistula 1

Diagnostic Approach

• The American College of Radiology recommends CT imaging with appropriate contrast as the primary diagnostic modality for suspected colovesical fistula 1, 2, 3
• CT with rectal or oral contrast with delayed scanning is useful to detect enterovesical fistulas and infected fistulous tracts 2, 3
• CT cystography has supplanted fluoroscopic cystogram for diagnosing bladder fistulas and leaks 2, 3
• MRI is equally sensitive to CT for evaluating enterovesicular fistulae with excellent soft-tissue contrast 4, 3

Common Etiologies

• Inflammatory bowel disease, such as Crohn's disease, is a common cause of colovesical fistula 5, 6

Critical Pitfalls to Avoid

• The American College of Radiology advises against relying on non-contrast CT alone for diagnosis, and recommends delayed imaging after contrast administration 1, 2, 3
• Consider adding rectal contrast when enterovesical fistula is in the differential 2, 3

Management Implications

• The American College of Radiology notes that CT cystography can provide additional information regarding size and location of the fistula for presurgical planning 3
• In patients with Crohn's disease and fistulas, the location matters for nutritional management, with distal fistulas potentially receiving enteral nutrition and proximal fistulas requiring partial or exclusive parenteral nutrition 6