the most common cause of colo - vesical ( cv ) fistulae is diverticular disease , followed by malignancy and crohn 's disease .
the preferred management of cv fistula is primary resection with anastomosis performed as a 1-stage procedure .
however , there are reports of patients with cv fistula secondary to diverticular disease managed medically for prolonged periods of time without operative intervention but without achieving complete healing .
this article reports a patient with a cv fistula , which healed without any surgical intervention . to the best of our knowledge , this has not been reported previously in the literature .
a 62-year - old gentleman with known diverticular disease presented to accident and emergency ( a&e ) in june 2009 with suprapubic pain , pyrexia , haematuria and elevated inflammatory markers .
he was treated with ciprofloxacin for a urinary tract infection ( uti ) and was discharged .
he was also being investigated for lower abdominal pain and weight loss by a colorectal surgeon .
a clinical diagnosis of diverticular abscess was made which was confirmed on computed tomography ( ct ) scan .
the ct images demonstrated moderate diverticular disease in the sigmoid colon with a 7  cm    6  cm abscess and a small pocket of air in the urinary bladder but no direct cv fistulous communication seen ( fig .
a subsequent flexible cystoscopy revealed a raised , inflamed area on the posterior wall of the urinary bladder .
the patient gave a past medical history of osteoarthritis , appendicectomy and transurethral resection of the prostate .
a colorectal multidisciplinary team meeting decided that he should undergo a hartmann 's procedure , which was performed on 13th july 2009 .
the intra - operative findings revealed an inflammatory mass involving the sigmoid colon , which was attached to the bladder and a segment of small bowel .
the involved small bowel segment was resected and a side - to - side anastomosis was performed .
the diseased segment of sigmoid colon was resected and a colostomy was fashioned in the left iliac fossa .
the histology of the sigmoid colon was consistent with diverticulitis and the resected small bowel specimen revealed features consistent with peritonitis , with no evidence of malignancy in either specimen .
the rectal stump was mobilised and anastomosed at approximately 16  cm from the anal verge using a stapling device .
one week following the reversal he presented to his general practitioner ( gp ) with rigours , fever , dysuria , macroscopic haematuria and pneumaturia .
a uti was diagnosed by analysing a midstream urine specimen ( msu ) , which subsequently grew mixed faecal flora .
three days later , on 11th february 2010 he was admitted as an emergency , now with suprapubic pain and faecaluria .
microbiology advice was sought and intravenous gentamicin and metronidazole was commenced in addition to clarithromycin and trimethoprim .
the ct images revealed a direct fistulous communication with the urinary bladder containing oral contrast with the presence of air in the bladder ( fig .
unfortunately , in august 2010 he saw his gp with further supra - pubic pain and dysuria .
an msu revealed wbcs  >  2000 with rbcs and a growth of escherichia coli .
3 ) which demonstrated no evidence of a collection and no air in the urinary bladder . the fat plane between the colon and the urinary bladder was intact .
he was reviewed on a final occasion in august 2013 and he remains asymptomatic . a ct scan done in september 2013 showed no communication between the bowel and urinary bladder and he was therefore discharged .
cv fistula is the most common type of fistula associated with diverticular disease of the colon .
diverticular fistulae occur when a phlegmon or abscess extends or ruptures into the adjacent bladder .
pneumaturia and faecaluria are common presenting symptoms and are considered pathognomic of a cv or an entero - vesical fistula .
the sensitivity of either cystoscopy or a barium enema in making the diagnosis of cv fistula is reported to be 3848% .
although useful in excluding other diagnoses , sigmoidoscopy and colonoscopy rarely permit visualisation of a fistula . staged surgical procedures remain the mainstay of cv fistula treatment .
there are case reports of cv fistulae treated conservatively because patients either did not want an operation or were too high a surgical risk .
only one case report documents complete healing of a procto - vesical fistula secondary to rectal cancer with the use of octreotide .
the authors postulate that octreotide reduces gastrointestinal tract secretions and therefore closure of the fistula may have been related to reduced inflow of gastrointestinal tract secretions into the bladder via the fistula .
six patients observed for 314 years encountered little inconvenience and were without significant complications while on intermittent antibacterial therapy alone . in another retrospective study ,
they were monitored over a 12-year period and were found to exhibit no significant changes in renal function and urosepticaemia was not documented . however
firstly , that he had a primary diverticular disease induced cv fistula at initial presentation , which came to light only after his reversal .
an alternative view is that it was an iatrogenic fistula that developed at the time of reversal of hartmann 's .
points supporting a primary fistula are that he had uti at first presentation , which is common in cv fistulae and rare in otherwise normal males .
patients with fistulae secondary to a benign cause tend to be commoner in men , suggesting that the uterus affords some protection against its formation in women .
secondly , cystoscopy demonstrated a raised inflamed area in the posterior wall of the urinary bladder suggestive of a cv fistula .
this gives credence to the second possibility of this being an iatrogenic fistula since it appeared after the reversal and with supportive radiological evidence .
there are reports of iatrogenic fistulae induced by surgical procedures , including colo - anal anastomoses augmentation cystoplasty , prostatectomy , rectal resections and laparoscopic inguinal hernia repair , or endoscopic procedures such as colorectal stenting for malignant obstruction . from the above examples ,
conservative management was documented in only one report , but this did not achieve complete healing .
whatever the aetiology this is the first time that such a fistula has been demonstrated clinically and radiologically to have healed spontaneously without surgery .
we would therefore suggest that in benign cv fistula resolution through conservative management might be considered as a first option , especially in those who , due to their co morbidities would be poor surgical candidates .
although some small studies have suggested that conservative management might be a reasonable option , no randomised controlled trials have supported conservative management . until such evidence becomes available careful selection with close follow - up
written informed consent was obtained from the patient for publication of this case report and accompanying images .
a copy of the written consent is available for review by the editor - in - chief of this journal on request .
 introductioncolo - vesical ( cv ) fistulae are the most common type of fistulae associated with diverticular disease . 
 surgery remains the mainstay of treatment , without which , cv fistulae rarely achieve complete healing.presentation of caseherein , we report the case of a 62-year - old man who developed a cv fistula after reversal of hartmann 's procedure ( initially for management of diverticular abscess ) , which healed with conservative management alone.discussionwe discuss possibilities of the aetiology of this fistula . 
 the cv fistula may have been initially present , which came to light only after his reversal . or an iatrogenic fistula that developed at the time of reversal of hartmann's.conclusionthis is the first time that such a fistula has been demonstrated clinically and radiologically to have healed spontaneously without surgery . 
 we recommend that conservative management of cv fistulae should be considered . 
Introduction
Case report
Discussion
Conclusion
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