Keywords
colovesical fistula - colonic diverticulosis - over-the-scope clip - combined endoscopy
Introduction
Colovesical fistula (CVF) is a pathological communication between colon, usually sigmoid
colon and urinary bladder dome. The incidence of CVF is estimated to be 2 to 4% with
male to female ratio of 3:1.[1]
The main cause of CVF is complicated diverticular disease in 65 to 79% of cases, followed
by advanced colonic and bladder cancer and Crohn’s disease. CVF is suspected clinically
based on pathognomonic features such as pneumaturia, fecaluria, and recurrent urinary
tract infection (UTI) but can be confirmed by cystoscopy, sigmoidoscopy, barium enema,
computed tomography (CT), or magnetic resonance imaging. The treatment of choice for
CVF is resection and anastomosis of the involved bowel segment and closure of the
bladder either by laparotomy or laparoscopy. Conservative treatment is reserved to
highly selected patients who are unfit for surgery.
The development of novel mechanical endoscopic closure systems allows for minimally
invasive management of CVF. Only a few cases of endoscopic management by clip closure
have been described in the literature. Here, we report a case of CVF, which was successfully
managed with over-the-scope clip (OTSC) in collaboration with urologist and medical
gastroenterologist.
Clinical Profile
An 86-year-old gentleman with a history of uncontrolled diabetes mellitus, hypertension,
and ischemic heart disease was presented to us with complaints of pneumaturia, recurrent
UTI, and occasional passage of feculent material in urine for the last 7 months. Clinical
examination was unremarkable except for mild tenderness in the lower abdomen. Investigations
showed marked leucocytosis, plenty of pus cells in the urine, and urine culture reported
Escherichia coli growth with significant colony count.
Ultrasound scan of abdomen demonstrated some echogenic material in the urinary bladder
and an inflammatory mass in the left iliac fossa. For the better delineation of the
pathology, we proceeded with contrast-enhanced CT scan of the abdomen that showed
diverticulosis of the sigmoid colon with a CVF ([Fig. 1]).
Fig. 1 Contrast-enhanced computed tomography scan of abdomen showing diverticulosis of the
sigmoid colon with a colovesical fistula (arrow).
Patient was a very high-risk candidate for anesthesia and his relatives were not willing
for surgery due to the risk. But in view of recurrent symptoms, he was planned for
OTSC closure of fistula. Unfortunately, due to multiple adjacent diverticula, the
exact location of fistulous opening in the colon could not be identified. Then with
the help of 20 Fr cystoscope, a 0.28-inch Terumo hydrophilic guide wire was passed
through the opening in the bladder to the sigmoid colon by the urologist. With an
adult flexible colonoscope (12.8 mm with 3.2 mm channel width), a 14/6t size OTSC
(Ovesco Endoscopy GmbH, Tuebingen, Germany) was deployed exactly over the fistulous
opening by the gastroenterologist ([Fig. 2]; [►Video 1]).
Video 1
Guide wire localization and OTSC closure of CVF. Online content including video sequences
viewable at: https://www.thieme-connect.com/products/ejournals/html/10.1055/s-0040-1715283.
Fig. 2 Colonoscopic pictures showing the guide wire coming through the fistula (A) and over-the-scope clip placement (B).
Antibiotics were continued, fecaluria and pneumaturia were settled down and he was
discharged after 1 week. Urine culture was sterile at 1 month postprocedure and he
became symptom free at 18 months.
Discussion
Enterovesical fistula is a pathological communication between bowel and urinary bladder
of which CVF is the most common type with incidence of 2 to 4%.[1] The occurrence of CVF is more in male patients when compared with female with a
ratio of 3:1. This variation could probably be due to the protective effect of uterus
in females by acting as barrier between rectum and bladder.[2]
Most commonly, CVF develops as a complication of diverticular disease in 65 to 79%
of cases. In 10 to 15% of cases, CVF is due to advanced colorectal carcinoma. Other
causes are Crohn’s disease (9.1%), surgical trauma (3.2%), and radiotherapy (3%).[3]
The diagnosis of CVF is primarily based on clinical evidence. Most common clinical
manifestation is pneumaturia reported in 50 to 70% of cases, followed by fecaluria
in 51%, dysuria in 45%, frequency in 45%, urgency and suprapubic pain. Low intravesical
pressure favors flow of fecal microbiota into the bladder causing recurrent UTI (45%),
hematuria (22%), and orchitis (10%).[4]
CT with both oral and intravenous contrast is the most sensitive investigation to
detect CVF with diagnostic accuracy of 90 to 100%. Other investigations include barium
enema, cystography, cystoscopy, and colonoscopy.[5]
Surgery is the treatment of choice for CVF. The choice of surgery depends on site
and etiology as well as the patient’s general condition. The standard surgical strategy
consists of resection of the involved bowel tract including fistula, primary or delayed
anastomosis, and closure of the bladder either by open approach or by laparoscopy[6] in patients who are unfit for major surgery due to poor overall health, patients
who are unable to tolerate general anesthesia, or in oncologic patients with short
life expectancy. A trial of medical therapy including bowel rest, total parenteral
nutrition, antibiotics, steroids, immunomodulatory drugs, and urethral catheter drainage
or palliative loop colostomy may be warranted.[7]
[8]
Morbidity from surgery ranges from 25 to 34%, with a 4.5 to 20% of perioperative mortality,[9] which has prompted a search for nonsurgical options like fibrin glue to occlude
the fistulous tract,[10] cautery probe through a specialized cystoscope to coagulate the bladder mucosa around
a fistula.[11] But according to literature, all these methods are effective mostly in upper gastrointestinal
fistulas. Due to poor blood supply of colon and due to surrounding inflammation, the
treatment of CVF is very difficult and surgery is the gold standard treatment. Currently,
the indications for treatment with OTSCs are primary or postinterventional bleeding
in the gastrointestinal tract, closure of iatrogenic full-thickness or covered perforations.[12] Even though more expensive than other methods, OTSC can be safely and effectively
employed for the treatment of CVF in patients who are unfit for surgery. But its success
depends on the exact localization of the fistulous opening. A few cases of endoscopic
closure of the colonic side of a CVF using through-the-scope or OTSC have been described
in the literature.[13]
[14]
Conclusion
We are reporting this case to make the surgical community aware about this previously
less described collaborative approach among surgeons, urologists, and gastroenterologists.
This combined endoscopic approach, which could be the first to be reported from India,
is found to be a safe and effective alternative in patients who are unfit for surgery.
However, further studies are needed to validate the potential benefits of this novel
endoscopic management.
