Fistula is the communication or contact between two epithelialized surfaces. Coming to colovesical fistula it is the presence of a communication among the lumen of the colon and that of the bladder, either directly or by indirect intervening abscess cavity. Colovesical fistula was the main general type of fistula related along with diverticular disease of the colon. Diverticular fistulae may happen when a phlegmon or abscess ruptures or extends to the adjacent bladder. Generally It will affects more men than women the ratio is like 3:1. Complicates 2-4% cases of diverticulitis, 67-80% fistulas may follow abdominal surgery.
Patients who are suffering with colovesical fistula may be asymptomatic but patients whose condition is chronic may have, refractory UTI and present with fecaluria, pneumaturia and patient may show signs of dehydration, physical exam which are usually not revealing.
The most common reason of colo-vesical (CV) fistulae is diverticular disease then followed by malignancy and Crohn’s disease. Prior abdominal operation, especially for inflammatory bowel disease, extensive adhesions, abscesses, anastomotic leaks Diverticular disease, radiation, trauma-Foreign body, malnutrition is also main risk factor in fistula formation/failure to heal.
Sigmoidoscopy is usually undetectable, but it may reveal the inflammation or mass at the fistula site
CT will detect small amounts of air in bladder
Contrast enema may detect large fistulas but commonly misses small openings
Fistulogram if tract is mature
Pyelography and cystography may be used to discern connection with urinary tract
Surgical resection of the fistula and abnormal segment of bowel is usually required for cure, although in the setting of malignancy this suggests advanced disease (T4) making surgery complex. In such cases, if palliation only is required then defunctioning colostomy, colonic stent placement or a nephrostomy may be required.