Case Series on Colovesical Fistula
Dr. Baiju Senadhipan MBBS 1, Dr. Devipriya Rajendran MS 2, Dr. Remadevi MS 2, Dr.Saividhya MBBS 2
*Correspondence to: Dr. Baiju Senadhipan MBBS, MS, DNB, MCH (Surgical Gastro), MNAMS, FMAS, HOD, Department of GI and HPB surgery, SK hospital, Trivandrum, Kerala.
Copyright
© 2026 Dr. Baiju Senadhipan, This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Received: 15 June 2026
Published: 01 July 2026
DOI: https://doi.org/10.5281/zenodo.21092851
Abstract
Introduction: Colovesical fistulas are relatively rare but can lead to significant complications. The etiological factors are diverticulitis (approximately two-thirds of cases), malignancy, primarily colonic adeno carcinoma. Crohn’s disease, post-surgical injury, trauma, abdominal tuberculosis, and pelvic irradiation can also cause colovesical fistula. These fistulas predominantly affect individuals aged 55 to 75 years, with a higher incidence in males and females with prior hysterectomies.
Methods: We present a series of five cases of colovesical and related fistulas, operated on 2017 to 2024 at SK Hospital, Trivandrum. The cases represent a small fraction of our monthly OPD. The study included 3 males and 2 females, with the majority aged 55-80 years. The most common presenting symptom was lower abdominal discomfort (100%), with other symptoms including increased urinary frequency, pneumaturia, and incomplete defecation. Preoperative contrast CT scans were performed for all cases, and intraoperative cystoscopy was done when indicated.
Results: The most common cause of fistula formation was diverticulitis (40%), followed by carcinoma of the bladder, pelvic abscess, and urachal cyst (each 20%). All surgeries were performed laparoscopically. Surgical interventions included ileocecal resection, low anterior resection, fistula excision, and bladder closure.
Conclusion: Our study supports the increasing preference for single-stage laparoscopic surgery in managing colovesical and related fistulas, emphasizing its advantages in recovery time, reduced complications, and patient outcomes. The findings align with the growing trend towards minimally invasive techniques and suggest that laparoscopic surgery may be a preferable option compared to traditional open methods. Further large-scale studies are needed to validate these findings.
Introduction
Rufus of Epheus first identified and explained about colovescical fistula in 200 AD and in 1888 first demonstrated by Cripps. (1) Majority of cases of colovesicular fistula occurs following diverticulitis (2), second most common cause is malignancy. The third most common etiology is Crohn’s colitis most probably long standing (5to 7%) (2). Other causes are Trauma, Post surgical iatrogenic injury, abdominal TB, pelvic irradiation.
Presentation of colovesicular fistula ranges from the age group of 55 to 75 years with male predominance (3), in females with prior hysterectomy the incidence is on the upper end (4).
Methods
We present a series of five cases presented as fistula from colon to adjacent organs like bladder and vagina. These were the cases operated from 2017 to 2024 in SK Hospital, Trivandrum. The incidence is still low accounting for only 5 cases out the entire OPD of about 150 cases per month.
3/5 were males and 2/5 were females.2/5 were in the age group 40-55 years.3/5 were in the age group 55 to 80 years. Most common presenting symptom was lower abdominal discomfort (100%). 3 patients presented with increased frequency of mictuirition , pneumaturia and incomplete defecation (60%) .1 patient presented with Reddish discoloration of urine (20%). Occasional fever was also a presenting symptom in almost all cases.
Regarding significant past history, one patient had previous H/O sigmoid diverticulitis with colovescical fistula, undergone low anterior resection and bladder cuff excision. After 5 years, the patient presented with rectovaginal fistula. A patient who had pelvic abscess with bladder adhesion had H/O appendicectomy done 1 year back. Another patient was a known Carcinoma bladder with infiltration to ceacum, diagnosed in other hospital and referred to us for further management.
Investigation: Preoperative contrast CT abdomen and pelvis was done for all the cases. Intraoperative cystoscopy was done for indicated cases. The most common cause of the fistula formation was Diverticulitis (40%). Other causes were carcinoma bladder, pelvic abscess and urachal cyst (each 20 %).
Management
All the cases were operated laparoscopically .Carcinoma bladder with ceacal infiltration was managed with bilateral DJ stenting, cystoscopy, bladder biopsy, tumour excision with bladder wall was done and rent closed in two layers followed by ileocecal resection followed by ileocolic anastomosis . For sigmoid diverticulitis –Laparoscopic low anterior resection, excision of the fistulous tract with bladder cuff excision was done. Urachal cyst was with fistulous connection to urinary bladder. Cyst excision done and cyst extracted via umbilical port. Supra pubic abscess was dissected from anterior abdominal wall adhesions. Since the wall was adherent to the bladder wall, bladder wall excised and closed in two layers. Rectovaginal fistula - intraoperative methylene blue was injected and found to be a sinus with no rectal connection. Intraoperative colonoscopy was done no fistulous opening was seen and it was found to be a rectovaginal sinus. Vaginal opening closed with vicarly and rectal sinus closed in single layer.
Discussion
Colovesical fistula have been reported more than 1000 cases in the last 30 years, still there is a lack of management protocol. Pollard SG et al states that most common cause of colovesical fistula was diverticular disease (56.3%). Other causes are carcinoma of colon (20.1 %), Crohn’s disease (9.1 %), surgeries (3.2%), radiotherapy (3%) and carcinoma of the cervix, carcinoma bladder and appendicitis accounting for the remainder (5). In our study, also most common cause of fistula formation was Diverticulitis (40%). Other causes were carcinoma bladder, pelvic abscess and urachal cyst (each 20%).
According to Kovalcik PJ et al, regarding the incidence in males and females, due to interposition of uterus the incidence is less in females, but in post hysterectomy status both show equal incidence (6). In our study one female patient had a history of hysterectomy and hence the incidence is 50% in post hysterectomy patient. Although the sample size taken for study is small, post hysterectomy shows significant incidence of colovescical fistula.
In comparing the findings of Najjar SF et al. and Kevin Seeras et al. with the results from our study, there are notable similarities and differences that warrant further discussion. Najjar SF et al. highlight that the most common presenting features of colovesical fistula are pneumaturia (77-90%), dysuria (45%), fecaluria (36%), hematuria (22%), orchitis (10%), and abdominal pain and diarrhea (7,8). While these findings align with established clinical expectations for colovesical fistulas, the most common presenting complaint in our study was lower abdominal pain and discomfort, reported by 100% of the patients. This discrepancy suggests that while the classic urinary and gastrointestinal symptoms are frequently observed in other studies, patients in our cohort might have presented with more localized, non-specific symptoms at initial presentation.
It is also possible that the presence of urinary symptoms such as pneumaturia and dysuria were either not sufficiently highlighted or were underreported in our patient population.
Kevin Seeras et al. attribute the majority of colovesical fistulas to complications arising from diverticulitis.[9] Our study corroborates this finding, as the most common cause of colovesicular fistulas in our cohort was also diverticulitis. This consistent observation emphasizes the critical role of diverticulitis in the pathogenesis of colovesical fistulas, suggesting that early detection and management of diverticular disease could potentially reduce the incidence of fistula formation.
Golabek T et al. suggest that the first and best diagnostic test for colovesical fistulas is a CT scan with oral or rectal contrast, without the need for intravenous contrast, noting that this method has greater than 90% accuracy. [10] This recommendation is consistent with the broader body of literature, which supports the use of CT scans as the gold standard for diagnosing colovesical fistulas due to their high sensitivity in detecting the fistulous tract and associated complications. Our study also employed contrast CT abdomen as a key diagnostic tool.
Additionally, while Golabek T et al. emphasize the role of CT scans, they also point to the importance of other diagnostic modalities such as colonoscopy and cystoscopy. [10] In evaluating the findings of Scozzari G et al. regarding the role of colonoscopy in detecting colovesical fistulas, it is important to consider the implications of their statement that colonoscopy has a relatively low sensitivity (ranging from 11% to 89%) for detecting the fistulous tract. [11]
In our study, we also incorporated colonoscopy as part of the diagnostic workup, which provided valuable insights into the condition of the colon and allowed for the detection of underlying pathologies like diverticulitis, which was the most common cause of colovesical fistula in our cohort. Colonoscopy offers a direct visual assessment of the mucosal surface and aids in identifying any structural abnormalities or inflammatory changes that might predispose to fistula formation.
Cystoscopy, as noted in our study, was similarly valuable in guiding the management of colovesical fistulas. While not universally utilized in all cases, it proved essential in cases where the bladder was directly involved in the fistulous tract.
McConnell DB et al. provide a historical perspective, noting that the traditional approach for these conditions often involved a three-stage resection, particularly in cases with complications such as abscess formation, intestinal obstruction, or a history of radiotherapy. This approach, which has been advocated by Charles Mayo, typically included a preliminary defunctioning colostomy, followed by staged resections. McConnell DB et al. recommend a 4-6 week interval between the stages for optimal recovery. [12].However, single stage procedures are done nowadays. . Similarly, Mileski WJ's observations about the growing preference for single-stage operations and laparoscopic surgery align with current trends. He emphasizes that there is no increased risk of morbidity or mortality when compared to staged procedures, making single-stage operations the favored approach for most patients. [13]
Regarding management, the approach in our study primarily involved surgical intervention, specifically one-stage resection of the fistulous tract. The laparoscopic approach allowed for reduced recovery times, smaller incisions, and less postoperative pain, aligning with the findings of Mileski WJ and others advocating for laparoscopic resections yet to be confirmed by many more trials.(14)
In our cohort, various complex cases were managed effectively using a single-stage laparoscopic approach. Notably, we encountered a carcinoma of the bladder with ceacal infiltration, which was managed with bilateral DJ stenting, cystoscopy, bladder biopsy, and tumor excision. The excision included the bladder wall, which was then closed in two layers, followed by an ileocecal resection and ileocolic anastomosis.
For cases of sigmoid diverticulitis, we performed a low anterior resection with excision of the fistulous tract and bladder cuff excision. Laparoscopic surgery facilitated the precise dissection of the fistulous tract and efficient resection. Additionally, in cases like the urachal cyst with a fistulous connection to the urinary bladder, we successfully extracted the cyst through the umbilical port, demonstrating the flexibility of laparoscopic techniques in managing various intra-abdominal pathologies.
In cases of supra-pubic abscesses, the laparoscopic approach enabled meticulous dissection from the anterior abdominal wall, with careful management of bladder wall adhesions. The bladder wall was excised and closed in two layers to ensure a secure repair. For the rectovaginal fistula, intraoperative methylene blue was used to confirm the absence of a direct rectal connection, with intraoperative colonoscopy further confirming that the condition was a rectovaginal sinus rather than a fistula. The rectal sinus was closed in a single layer, and the vaginal opening was closed with Vicryl, completing the repair.
Conclusion
Our study reaffirms the growing trend towards single-stage laparoscopic surgery in the management of colovesical and related fistulas. It offers significant advantages in terms of recovery time, reduced complication rates, and overall patient outcomes.
Our findings support the continued shift away from multi-stage procedures in favor of more streamlined, minimally invasive techniques. Further studies, particularly large, multicenter randomized trials, are needed to validate the long-term benefits of laparoscopic surgery over traditional open techniques, but our experience aligns with the growing body of evidence advocating for its widespread use.
References