By defnition, a fistula is an extra- anatomic, epithelialized tract between two hollow organs or between a hollow organ and the body surface. In case of urethrorectal fistulas, the tract occur between the urethra and the rectum.
urethrorectal fistulas may be congenital (associated with imperforate anus & extremely rare) or acquired (iatrogenic or non- iatrogenic ).
Acquired urethrorectal fistulas are typically associated with iatrogenic injury during pelvic surgical procedures and uncommonly associated with pelvic radiotherapy. Prtedisposing factors for post- prostatectomy urethrorectal fistulas are: radiation, previous rectal surgery, or TURP.
Iatrogenic causes of URFs include:1. Radical Prostatectectomy (RP) Incidence of Rectal injury during RP is less than 1 - 2%, However, it is considered the most common cause due to increased number of radical prostatectomies done yearly.
2. Local treatments for prostatic cancer: including Radiotherapy, Brachytherapy (0.4%), Cryotherapy (0.5 to 2%) or HIFU.3. Open prostatectomy or TURP or overly aggressive TUR of bladder neck contracture.4. Anorectal surgery: abdomino-perineal resect.5. Urethral instrumentation is also a rare cause of urethrorecal fistula
Patient with URF can be presented by: Fecaluria. Hematuria. Recurrent UTI refractory to treatment . Peritonitis and sepsis. Fever, Nausea and vomiting.
Digital rectal examination (DRE): during rectal examination fistula track can be felt along the anterior rectal wall. Cystoscopy and sigmoidoscopy can be used for visualization of the fistula track & biopsy for detection of malignancy. Upper tract imaging can be used to exclude a related ureteral injury.
Diagnosis of rectourethral fistula can be confirmed with RUG or VCUG.
Conservative treatment can cure some cases of post- prostatectomy URFs (open or laparoscopic). Conservative treatment include catheter drainage, NPO, IV Total parentral nutrition, anal dilatation and Antibiotics
Fecal diversion may be needed in urethrorectal fistulas after brachytherapy or cryosurgry. repair of such fistulas is quiet difficult because it is usually large with induration, fibrosis and ischemia.
Surgery is the main line of treatment in most of cases of urethrorectal fistulas. It can be performed as single stage or staged repair. Some authors have advocated fecal diversion and staged repair of all URFs.
Staged repair is done with fecal diversionperformed before repair of the rectourethralfistula.Staged repair is indicated in: large fistulas, post-radiation therapy, uncontrolled local or systemic infection, Immunocompromised, inadequate bowel preparation at initial oper.
performed in a prone jackknife position with the buttocks taped laterally. Incision is performed from the sacrococcygeal juncture to the anus.
incision is deepened through the posterior anus and dorsal rectal wall and deepened down to the level of the coccyx through the external anal sphincter
The fistula track is excised, and the anterior rectal wall is mobilized circumferentially around the fistula margins. The urethra is closed. Anterior rectal wall is closed. Rectal mucosa is re- approximated This provides 3-layer closure. reapproximating the post. rectal wall & anal sphincter.
Results of York-Mason procedure are excellent. Based upon literature reports, the York-Mason approach has become the favored repair for URFs not amenable to a transanal approach. Renschler and Middleton in 2003 reported a successful repair in 22 of 24 patients. No serious complications were reported, and no patient developed anal incontinence or stenosis. Similar excellent results have been noted by other authors ( Prasad et al, 1983 ; Bukowski et al, 1995 ; Fengler and Abcarian, 1997) .
A perineal approach to rectourethral fistula has been described in selected cases with good results. Advocated by: Bukowski et al, 1995. Nyam and Pemberton, 1999. Youssef et al, 1999. Zmora et al, 2003.
Advantages of perineal approach include: being a familiar approach for many urologists and local accessability to a variety of potential interpositional flaps. Perineal approach with interpositional flap provided Excellent results.
Interposition grafts include: Gracilis muscle: Ryan et al, 1979 ; Rius et al, 2000 ; Zmora et al, 2003. Pedicled dartos muscle: Venable, 1989 ; Youssef et al, 1999 ; Yamazaki et al, 2001. Penile skin: Morgan, 1975. levator muscle: Goodwin et al, 1958. Bladder: Kokotas and Kontogeorgos, 1983.
patient in the extended lithotomy position. a 20 F 30-ml filled balloon catheter is inserted. Use retractors to bring fistula into the wound, and insert a finger into the rectum as a guide. Divide the fistula and excise all surrounding scar tissue.
Graft can be interposed between urethra & rectum esp. in teneous repair. urethral defect is closed in two layers with 4-0 absorbable suture.
Transabdominal approach has been described for URF rapair with limited success. Advocated by: Bukowski et al, 1995 ; Nyam and Pemberton, 1999 ; Shin et al, 2000. The principal advantage to this technique is the availability of greater omentum for an interpositional flap.
Potential disadvantages include: morbidity and prolonged postoperative convalescence associated with a laparotomy incision the poor exposure of the operative field limited maneuverability in the deep pelvis risk of urinary and fecal incontinence.
Continue antibiotic administration and a low- residue diet postoperatively. Shorten the drain in 3 days and remove it the next day. Remove the catheter or cystostomy no sooner than the 8th day.