KEY POINTS
- Surgical risk factors include prior pelvic surgery, history of pelvic inflammatory disease, pelvic malignancy, endometriosis, infection, diabetes, and anatomic distortion.
- Conservative therapy should be reserved for simple fistulae that are less than 1 cm in size, diagnosed within 7 days of the index surgery, lacking associated carcinoma or radiation, and subject to at least 4 weeks of constant bladder drainage.
- In surgical repair, the Latzko partial colpocleisis or fistulectomy with flap-splitting closure is preferred.
Recent advances have improved the success of vesicovaginal fistula (VVF) repair—a challenge that can test even the most experienced gynecologic surgeon. For example, it now is apparent that some small uncomplicated fistulae respond to conservative treatment. Further, in selected cases, laparoscopic repair can eliminate the need for complicated laparotomy.
In addition, timing of fistula repair no longer requires long periods of observation, and good surgical technique for identifying and repairing bladder injuries at the time of the index surgery can often prevent the development or reduce the severity of VVF.
Vesicovaginal fistula is the most common type of urogenital fistula. Presentation and prognosis vary, depending on location and size of the defect, as well as coexisting factors such as tissue devascularization and previous radiation. However, surgical repair is associated with a high cure rate if it is performed by an experienced surgeon.
Most US cases follow gynecologic surgery
Vesicovaginal fistula was first documented in the mummified remains of Egyptian Queen Henhenit (11th Dynasty, 2050 BC), which were examined in 1923 by Derry.1 Although the exact incidence of VVF in the United States is unknown, the primary cause is gynecologic surgery, especially hysterectomy. The defect is estimated to occur in 0.01% to 0.04% of gynecologic procedures.
A study of 303 women with genitourinary fistula found that the defect was related to gynecologic surgery in 82% of cases, obstetric events in 8%, radiation therapy in 6%, and trauma or fulguration in 4%.2 Rare causes of VVF include lymphogranuloma venereum, tuberculosis, syphilis, bladder stones, and a retained foreign body in the vagina. In rare instances, spontaneous vesicouterine fistulae were reported following uncomplicated vaginal birth after cesarean section.3
Gynecologic surgery may lead to VVF due to extensive dissection between the bladder and the uterus, unrecognized bladder laceration, inappropriate stitch placement, and/or devascularization injury to the tissue planes. Concurrent ureteric involvement has been reported in as many as 10% to 15% of vesicovaginal fistula cases.
In developing countries, vesicovaginal fistulae are far more common and generally related to obstetric factors such as obstructed labor (due to unattended deliveries), small pelvic dimensions, malpresentation, poor uterine contractions, and introital stenosis.
Risk factors. Conditions that may predispose patients to VVF include prior pelvic surgery, a history of pelvic inflammatory disease, pelvic malignancy, endometriosis, infection, diabetes, and anatomic distortion. If these risk factors are present, the patient should be counseled accordingly prior to gynecologic surgery.
Correct classification crucial to surgical success
Proper classification of VVF can help the gynecologic surgeon plan operative intervention. Obstetric vesicovaginal fistulae usually are categorized according to their cause, complexity, and site of obstruction. In contrast, gynecologic fistulae are generally classified as simple or complicated (TABLE).
These levels may have important implications for the surgical approach and prognosis.4 For example, simple vesicovaginal fistulae are usually uncomplicated surgical cases with good prognosis. Complicated vesicovaginal fistulae, on the other hand, can challenge even highly practiced and skilled gynecologic surgeons and are associated with a high rate of recurrence.
Women typically present within specific intervals after the various antecedent events (pelvic surgery, childbirth, radiation therapy) with a primary complaint of constant, painless urinary incontinence. If the fistula is related to traumatic childbirth, most patients experience urine leakage within the first 24 to 48 hours. Following pelvic surgery, symptoms usually occur within the first 30 days. In contrast, radiation-induced fistulae develop over a much longer interval secondary to progressive devascularization necrosis, and may present 30 days to 30 years after the antecedent event.
Some patients report exacerbation during physical activities, which can sometimes lead to erroneous diagnosis of uncomplicated stress incontinence. If the fistula is small, intermittent leakage with increased bladder distention or physical activity may be noted.
Other patients may complain of vaginal discharge or hematuria.
If there is concurrent ureteric involvement, the patient may experience constitutional symptoms (such as fever, chills, and flank pain) or even gastrointestinal symptoms.
Physical findings. Any pooling of fluid in the vagina that is noted should be sent for analysis if the diagnosis is unclear. Next, perform a careful speculum exam that allows visualization of the entire anterior vaginal wall to identify the fistula tract (FIGURE 1). In many cases, the fistula is grossly visible.