Colonic-Ureteral Fistula: Medical Management
There is no effective medication for treating a colonic-ureteral fistula—this condition requires surgical intervention, not pharmacotherapy. The role of medication is limited to managing infection and treating the underlying inflammatory bowel disease if present.
Critical Understanding: Why Medication Alone Fails
A colonic-ureteral fistula represents an abnormal communication between the colon and ureter, most commonly caused by colonic diverticulitis or Crohn's disease 1, 2. This is a structural problem that cannot be resolved with medication alone. The fistulous tract will not close spontaneously with antibiotics or anti-inflammatory drugs.
Immediate Medical Management (Pre-operative)
Infection Control
- Broad-spectrum antibiotics are essential to treat the inevitable urinary tract infection that accompanies this condition, as UTI occurs in 100% of cases 2
- Metronidazole 400 mg three times daily combined with ciprofloxacin 500 mg twice daily provides appropriate coverage for both colonic flora and urinary pathogens 3
- For severe infection requiring hospitalization, piperacillin-tazobactam 4g/500mg IV three times daily offers excellent coverage for complicated UTI with mixed colonic flora 4
If Crohn's Disease is the Underlying Cause
- Metronidazole 10-20 mg/kg/day (typically 400 mg three times daily) has a specific role in Crohn's-related fistulating disease, though it is not first-line therapy 3, 5
- Azathioprine 1.5-2.5 mg/kg/day or mercaptopurine 0.75-1.5 mg/kg/day may be effective for enterocutaneous fistulae where distal obstruction and abscess have been excluded, but these agents have slow onset of action 3
- Infliximab (three infusions of 5 mg/kg at 0,2, and 6 weeks) should be reserved for refractory fistulae and used as part of a strategy that includes surgery 3
Definitive Treatment: Surgical Intervention
Surgery is the only curative treatment for colonic-ureteral fistula 2. The typical approach involves:
- Resection of the diseased bowel segment with primary anastomosis when feasible 2
- Nephroureterectomy may be necessary if the kidney is non-functioning and infected 1, 2
- Surgical manipulation of the urinary system beyond removing a non-functioning kidney is generally unnecessary 2
Common Pitfalls to Avoid
- Do not delay surgical consultation while attempting prolonged medical management—these fistulae do not close with medication alone
- Do not miss the diagnosis—patients often have a protracted course (up to 10 years) before accurate diagnosis due to vague presentation 2
- Barium enema is the most reliable diagnostic test (75% sensitivity) compared to IVP (33%) or retrograde pyelogram (25%) 2
- The left ureter is involved in 75% of cases 2