Colovesical and Enterovesical Fistula Repair
An enterovesical fistula connects bowel to bladder; a colovesical fistula is the colon-specific subset. Diverticular disease is the commonest cause in adult surgical series, but Crohn's disease, malignancy, prior surgery and radiation require different treatment plans.[1][2][3] Definitive management addresses the diseased bowel and the bladder defect, with colorectal and urological planning appropriate to the anatomy.
For presentation and differential diagnosis see Colovesical / Small-Bowel Fistulas (clinical). For rectal fistulas after urological treatment see Transabdominal RUF / RVF Repair.
Confirm the cause and anatomy
Pneumaturia, fecaluria and recurrent urinary infection are characteristic. Pneumaturia also occurs after instrumentation or with gas-forming infection; a urine culture identifies organisms and guides treatment but does not establish a fistula by itself.[1][2]
| Investigation | Practical purpose and limitation |
|---|---|
| CT abdomen/pelvis | Define bowel and bladder involvement, abscess, obstruction and possible malignancy. A tract may not be directly visible; contrast protocol should fit the clinical question. |
| Colonic endoscopy | Assess the underlying bowel disease and exclude colorectal malignancy, usually after acute inflammation has settled; account for a recent adequate examination. Low direct tract detection does not make the examination unhelpful. |
| Cystoscopy, with biopsy of suspicious lesions | Evaluate suspected bladder malignancy, hematuria or uncertain bladder-side anatomy and the ureteric orifices. Use according to the clinical and operative question; failure to see a tract does not exclude the fistula. |
| MRI / enterography | Selected complex or inconclusive cases and Crohn's disease mapping. A small historical series is not a reliable universal MRI sensitivity estimate. |
| Poppy-seed test | Can demonstrate bowel-to-urinary communication but does not localize it or establish its cause. In Melchior's series it was positive in 35/37 tested patients, not a comparative modern diagnostic-accuracy trial. |
These roles are supported by clinical series and guideline-based evaluation; their reported test yields vary with selection and protocol.[2][4][6][8] A 2026 multicenter retrospective study of 101 surgically treated diverticular colovesical/colovaginal fistulas proposed a more focused workup. Its pathway is hypothesis-generating, not a requirement to perform every test or evidence that fewer tests cause better outcomes.[7]
Choose surgery or selected nonoperative treatment
Diverticular fistula: ASCRS recommends that elective colectomy typically be offered for diverticulitis complicated by fistula, obstruction or stricture (strong recommendation, moderate-quality evidence). Urgency and the operation depend on infection control, bowel pathology, fitness and goals of care.[8]
Crohn's fistula: coordinate with the IBD team. Drain an associated abscess and treat infection; persistent fistula-related symptoms, recurrent infection, obstruction or other complications can favor surgery. A fistula alone does not invariably require resection in a stable patient without these problems.[9] Do not require an anti-TNF trial before source control or promise that medical therapy will close most urinary fistulas.
The often-quoted 57% anti-TNF complete response comes from only 14 enterovesical cases in a 2016 systematic review. The review's 65.9% complete response pooled 44 enterovesical patients receiving various medical regimens; these are different denominators with low-quality, heterogeneous evidence. Five-year results from mixed internal-fistula cohorts should not be relabeled as enterovesical-specific outcomes.[9][10] In a separate 37-patient Crohn's series, 13 avoided surgery over a mean 4.7 years; sigmoid origin and associated complications were linked to eventual operation.[11]
For patients unable to undergo definitive resection, individualized symptom control or diversion may be appropriate. A stoma alone is not a reliable fistula-closure procedure, but palliation is a different objective from definitive repair.[3]
Prepare for reconstruction
Treat active urinary/systemic infection, assess and support nutrition, control drainable sepsis and optimize Crohn's inflammation with the treating team. Define ureteral involvement and anticipate whether bladder repair, ureteral reconstruction or an oncological resection will be needed.
In Chen's retrospective Crohn's series, all 74 patients underwent surgery. Urinary symptoms had resolved after preoperative optimization in 42; bladder repair was required in 9/42 versus 19/32 with persistent symptoms. This association supports careful preparation, but symptom resolution was not evidence of nonsurgical fistula closure or proof that optimization caused the difference.[5]
Operative principles
Bowel resection and continuity
For suitable patients with benign disease, resection of the diseased bowel and fistula takedown with primary anastomosis is commonly performed. Decide separately whether a protective stoma is needed. Significant contamination, physiological instability, poor tissue or nutritional status may require a staged strategy; abscess history alone does not prescribe a specific number of operations.[8][12][18]
Mobilize the involved bowel, identify and protect the ureters, and separate the inflammatory attachment under direct vision. Resection extent follows the underlying disease. Suspected malignant invasion requires oncological planning rather than assuming that a benign inflammatory plane can be separated safely.
Bladder-side decision
| Finding after bowel separation | Approach |
|---|---|
| Benign disease, no overt defect and negative bladder leak assessment | Catheter drainage without bladder suturing can be sufficient. |
| Visible full-thickness defect or leakage | Obtain a watertight absorbable-suture closure suited to the defect, available tissue and proximity to ureters. |
| Suspected malignancy, irradiated/nonviable tissue or trigonal/ureteral involvement | Plan the required excision and reconstruction individually; simple benign-fistula series do not establish the correct operation. |
Ferguson's 74-patient series used Foley drainage alone for the bladder in 68%, after resection of diseased bowel. It excluded abdominal cancer and pelvic radiation; the result does not mean 68% of all fistulas will heal with catheter drainage without bowel surgery.[13] A systematic review also supported omitting bladder repair after a negative intraoperative leak test in selected diverticular cases.[12]
Two-layer closure was used in a small eight-patient Crohn's series, but that series does not prove that two layers are required for every defect.[14] Catheter duration and the need for a cystogram depend on closure complexity, tissue quality and healing concerns. Published protocols include seven days in Ferguson's benign series and approximately two weeks in Yamamoto's Crohn's series; neither establishes a universal schedule.[13][17]
Interposition and ureteral identification
Vascularized tissue may be useful to separate difficult repairs, particularly when local tissue is compromised. Routine omental interposition has not been shown in comparative fistula trials to prevent recurrence in every case. Perivesical fat rotation is a described alternative with limited case-based evidence.[15][16]
Selective ureteral catheters or fluorescence can assist identification in distorted anatomy. In a robotic series, ureteral ICG was used in 44%; this uncontrolled observation does not demonstrate prevention of ureteral injury.[22]
Open, laparoscopic and robotic approaches
ASCRS favors minimally invasive colectomy for diverticulitis when expertise is available. Fistula-specific comparisons remain predominantly retrospective and must account for disease complexity and selection.[8]
| Evidence | Observed result | Interpretation |
|---|---|---|
| Trejo-Avila 2021: five retrospective studies, 227 diverticular CVF patients | Laparoscopy versus open: overall complications OR 0.55 (95% CI 0.30–0.99); stay about 2.9 days shorter; laparoscopic conversion 36% | No statistically significant difference in leak, mortality or stoma rates; this does not establish equivalence. |
| Volkert 2025: propensity-matched national inpatient analysis | Stay 6.9 days MIS versus 7.3 days open; no significant difference in mortality, wound complications or postoperative sepsis/shock | Administrative observational data; the OR 0.55 above comes from Trejo-Avila, not this study. |
| Sassun 2025: 89 robotic diverticular fistula resections | 58 colovesical, 26 colovaginal, five both; one conversion, one bladder leak and one fistula recurrence; median follow-up 16.5 months | Mixed fistula types, one center, no concurrent laparoscopic comparator. Cannot establish robotic superiority from comparison with older laparoscopic series. |
Sources: Trejo-Avila,[20] Volkert,[19] Sassun.[22] A separate 11-patient laparoscopic series associated posterior bladder location with conversion; its size limits prediction for an individual patient.[21]
Outcomes and salvage
A systematic review of 14 contemporary reports comprising 1,061 diverticular CVF patients reported major complications in 7.4%, mortality in 1.5% and recurrence in 0.5%. These aggregate observational results do not apply interchangeably to Crohn's, cancer or irradiated fistulas.[12]
In Yamamoto's Crohn's series, 25 of 30 patients underwent surgery. Three developed early septic complications and later recurrent bladder fistulas over median 13-year follow-up; this differs from short-term benign diverticular recurrence estimates.[17] Chen reported one early bladder leak and three recurrent bladder fistulas among 74 surgically treated Crohn's patients.[5]
Over-the-scope clips may be considered for selected patients with contraindications to conventional surgery. In DeLong's ten-patient mixed colovesical, rectovesical and vaginal-fistula series, placement was technically successful in eight; durable closure after the first intervention occurred in 4/8 treated patients. One further patient succeeded after four interventions. This small series does not establish a 50% cure rate for all enterovesical fistulas.[23]
Recurrent urinary symptoms, fever, fecaluria or pneumaturia after repair warrant reassessment for persistent communication, infection and underlying bowel disease. Durable management depends on disease control as well as closure of the tract.
References
1. Daniels IR, Bekdash B, Scott HJ, Marks CG, Donaldson DR. "Diagnostic lessons learnt from a series of enterovesical fistulae." Colorectal Dis. 2002;4(6):459–462. doi:10.1046/j.1463-1318.2002.00370.x
2. Najjar SF, Jamal MK, Savas JF, Miller TA. "The spectrum of colovesical fistula and diagnostic paradigm." Am J Surg. 2004;188(5):617–621. doi:10.1016/j.amjsurg.2004.08.016
3. Moss RL, Ryan JA. "Management of enterovesical fistulas." Am J Surg. 1990;159(5):514–517. doi:10.1016/s0002-9610(05)81259-0
4. Melchior S, Cudovic D, Jones J, et al. "Diagnosis and surgical management of colovesical fistulas due to sigmoid diverticulitis." J Urol. 2009;182(3):978–982. doi:10.1016/j.juro.2009.05.022
5. Chen Y, Cao L, Qiu J, et al. "Surgical management and outcome of entero-urinary fistula complicating Crohn's disease: a single center study." World J Surg. 2023;47(12):3365–3372. doi:10.1007/s00268-023-07196-x
6. Tjandra D, Garg M, Behrenbruch C, et al. "Review article: investigation and management of internal fistulae in Crohn's disease." Aliment Pharmacol Ther. 2021;53(10):1064–1079. doi:10.1111/apt.16326
7. Zimniak L, Ritz JP, Wullstein C, et al. "The diagnostic journey in fistulizing sigmoid diverticulitis: a multicenter retrospective study and proposal for a structured workup." Dig Dis. 2026;44(2):147–155. doi:10.1159/000549576
8. Hall J, Hardiman K, Lee S, et al. "The American Society of Colon and Rectal Surgeons clinical practice guidelines for the treatment of left-sided colonic diverticulitis." Dis Colon Rectum. 2020;63(6):728–747. doi:10.1097/DCR.0000000000001679
9. Lightner AL, Vogel JD, Carmichael JC, et al. "The American Society of Colon and Rectal Surgeons clinical practice guidelines for the surgical management of Crohn's disease." Dis Colon Rectum. 2020;63(8):1028–1052. doi:10.1097/DCR.0000000000001716
10. Kaimakliotis P, Simillis C, Harbord M, et al. "A systematic review assessing medical treatment for rectovaginal and enterovesical fistulae in Crohn's disease." J Clin Gastroenterol. 2016;50(9):714–721. doi:10.1097/MCG.0000000000000607
11. Zhang W, Zhu W, Li Y, et al. "The respective role of medical and surgical therapy for enterovesical fistula in Crohn's disease." J Clin Gastroenterol. 2014;48(8):708–711. doi:10.1097/MCG.0000000000000040
12. Froiio C, Bernardi D, Asti E, et al. "Burden of colovesical fistula and changing treatment pathways: a systematic literature review." Surg Laparosc Endosc Percutan Tech. 2022;32(5):577–585. doi:10.1097/SLE.0000000000001099
13. Ferguson GG, Lee EW, Hunt SR, Ridley CH, Brandes SB. "Management of the bladder during surgical treatment of enterovesical fistulas from benign bowel disease." J Am Coll Surg. 2008;207(4):569–572. doi:10.1016/j.jamcollsurg.2008.05.006
14. Gruner JS, Sehon JK, Johnson LW. "Diagnosis and management of enterovesical fistulas in patients with Crohn's disease." Am Surg. 2002;68(8):714–719. doi:10.1177/000313480206800811
15. Hwang A, Watson M, Talluri S, Okafor H, Singh A. "A novel perivesical fat rotational flap as an alternative to omental interposition in challenging urological reconstruction." Urology. 2023;182:e262–e263. doi:10.1016/j.urology.2023.08.023
16. O'Leary DP. "Use of the greater omentum in colorectal surgery." Dis Colon Rectum. 1999;42(4):533–539. doi:10.1007/BF02234183
17. Yamamoto T, Keighley MR. "Enterovesical fistulas complicating Crohn's disease: clinicopathological features and management." Int J Colorectal Dis. 2000;15(4):211–215. doi:10.1007/s003840000233
18. El-Haddad HM, Kassem MI, Sabry AA, Abouelfotouh A. "Surgical protocol and outcome for sigmoidovesical fistula secondary to diverticular disease of the left colon: a retrospective cohort study." Int J Surg. 2018;56:115–123. doi:10.1016/j.ijsu.2018.05.742
19. Volkert A, Nigam A, Stover D, et al. "Comparison of open versus minimally invasive repair of colovesical fistula: a case report and propensity-matched national database analysis." J Clin Med. 2025;14(17):6065. doi:10.3390/jcm14176065
20. Trejo-Avila M, Vergara-Fernández O. "Open versus laparoscopic surgery for the treatment of diverticular colovesical fistulas: a systematic review and meta-analysis." ANZ J Surg. 2021;91(9):E570–E577. doi:10.1111/ans.16985
21. Kitaguchi D, Enomoto T, Ohara Y, et al. "Laparoscopic surgery for diverticular colovesical fistula: single-center experience of 11 cases." BMC Res Notes. 2020;13(1):177. doi:10.1186/s13104-020-05022-4
22. Sassun R, Sileo A, Ng JC, et al. "Diverticular disease complicated by colovesical and colovaginal fistulas: not so complex robotically." Surg Endosc. 2025;39(6):3941–3946. doi:10.1007/s00464-025-11754-w
23. DeLong CG, Scow JS, Morrell DJ, et al. "Endoscopic management of colovesical and colovaginal fistulas with over-the-scope clips." Colorectal Dis. 2022;24(3):314–321. doi:10.1111/codi.15987