Vaginal Fistula
last authored: July 2011, Marissa Vance
last reviewed: July 2011, Dan Reilly
Introduction
Vaginal fistula is an abnormal opening between the vagina and another organ, usually the bladder or rectum. This preventable and treatable condition affects between 50,000-100,000 women yearly, though an estimated 2 million women remain living with it, mostly in sub-Saharan Africa and Asia (UNFPA, 2011). The condition, which leads to involuntary, ongoing release of urine or feces, is disastrous if unrepaired, often leaving women as outcasts. However, fistula is usually preventable through identification of obstructed labour and prompt referral for C-section. It is also easily repairable in the majority of cases.
A vesicovaginal fistula (VVF) is an abnormal communication between the vagina and the urinary bladder, which results in an involuntary release of urine into the vagina (Spurlock, 2011). A rectovaginal fistula (RVF) is an abnormal communication between the vagina and the rectum, which results in an involuntary discharge of fecal content &/or flatulence into the vagina (Taylor, 2011).
The Case of Shelly R
Shelly R is a 38 year old G2P2 presents to your office with continuous urine leakage for the past week. She had a total laparoscopic hysterectomy 3 weeks ago.
- how do you diagnose her problem?
- how might you treat it?
Causes and Risk Factors
Vaginal fistulas most often occur following obstetric trauma (in which case, the vaginal fistula may also be referred to as an obstetric fistula), or due to pelvic surgery. They very rarely arise from developmental abnormalities.
“The sun should not rise or set
twice on a labouring woman”
—African proverb
Obstetrical trauma, most often caused by prolonged &/or obstructed labour, is the most common etiology of vaginal fistulas in developing countries. Obstructed labour, sometimes lasting up to five days, causes prolonged pressure of the fetal presenting part against the anterior vaginal wall and bladder/rectum, leading to ischemia and necrosis which can then lead to fistula formation. The baby usually dies as a part of this process (Endfistula.org).
Risk factors for obstructed labour include:
- young age at childbirth (pelvis not fully grown)
- malnutrition
- female circumcision (can cause a more narrow vaginal introitus)
The use of instruments during obstructed labour, such as forceps, may also cause vaginal trauma leading to fistula formation. Perianal lacerations due to episiotomy may increase the likelihood of developing an RVF (Taylor, 2011).
Pelvic surgery is the most common etiology of vaginal fistulas in developed countries, more commonly causing VVFs than RVFs. Hysterectomies are the most common cause of VVFs, with laparoscopic hysterectomies having a greater incidence than either abdominal or vaginal hysterectomies (Schorge, 2008). Other pelvic surgeries that may cause inadvertent bladder trauma leading to fistula formation are suburethral sling procedures, urologic, and gastrointestinal surgeries (Spurlock, 2011).
There are many other causes of vaginal fistulas, including (Spurlock, 2011, Taylor, 2011, Schorge, 2008):
- vaginal trauma
- radiation therapy
- malignancy
- foreign bodies (ex. neglected pessary)
- pelvic inflammation
- infections
- inflammatory bowel disease
Risk factors for vaginal fistula formation are conditions that interfere with healing (Spurlock, 2011 and Schorge, 2008). Such conditions may include:
- chronic steroid use
- smoking
- poorly controlled diabetes mellitus
- infection
- malignancy
Pathophysiology
Fistulas often occur following injury to the vaginal tissue. Fistulas may form simply due to tissue damage and necrosis themselves. However, tissue damage and necrosis also induces inflammation at the injury site, which stimulates the process of cell regeneration. Any disruption in the sequence of cell regeneration can also cause fistula formation. Such disruptions can include hypoxia, ischemia, malnutrition, radiation, or chemotherapy affecting the healing environment.
A chronic fistula tract is created when the edges of the injury eventually epithelialize, which can be weeks or more following the tissue injury.
Signs and Symptoms
- history
- physical exam
History
The clinical presentation is often helpful in identifying the type of vaginal fistula.
The classical presentation of VVF is an unexplained, continual leakage of urine from the vagina.
An RVF often presents as passage of flatulence &/or stool through the vagina.
Additional symptoms of VVFs and RVFs may include:
- vaginitis
- cystitis
- new or increased vaginal discharge
- foul-smelling vaginal discharge
History should include information regarding obstetrical deliveries, pelvic surgeries, past history of fistulas, and any malignancy &/or treatment of malignancy.
Physical Exam
Visual inspection during physical examination is often able to identify the defect causing the fistula.
Vaginoscopy (laparoscope inserted into the vagina, with the vaginal walls being held open by a transparent plastic speculum) can be used as well for fistula identification. In the case of a VVF, physicians should be sure to differentiate urine leakage from a vaginal fistula versus stress incontinence on physical exam.
In the case of an RVF, a rectovaginal examination and proctosigmoidoscopy are useful in determining the diagnosis, size, and location of an RVF.
Once a vaginal fistula is found on examination, the degree of tissue inflammation, edema, and infection should be evaluated, along with the determination of the accessibility of the fistula for repair.
Dye instillation is a procedure that can be done to confirm the presence of either a VVF or a RVF. During the test, gauze or a tampon is inserted into the vaginal canal. A solution of diluted methylene blue or indigo carmine is instilled into either the bladder or the rectum. The patient then participates in 15-30 minutes of regular activity. After that time, the gauze/tampon is removed and examined for coloured dye. The area that the dye is found on the gauze/tampon may also help to indicate the level the fistula is at in the vagina (Taylor, 2011).
Investigations
- lab investigations
- diagnostic imaging
Lab Investigations
Lab investigations for VVF include testing any fluid collected for urea, creatinine or potassium (helps to differentiate vaginal fluid from urine). Urine should be collected and sent for culture & sensitivity.
Lab investigations for RVF includes a CBC to check for sepsis.
Diagnostic Imaging
Imaging required before VVF repair includes:
- intravenous urogram (IVU) to exclude ureter injury
- retrograde ureteropyelography at the time of cystoscopy may also be done to check for ureter injury
Imaging for an RVF includes:
- barium enema
- CT scanning
Differential Diagnosis
Differential diagnosis for a VVF:
- urinary incontinence
- fistula between the urinary tract & the cervix
- fistula between the urinary tract & the uterus
- fistula between the urinary tract & the fallopian tubes
Treatments
Vaginal fistulas may be treated with medical therapy or surgical therapy.
Medical therapy for a VVF involves constant bladder drainage using an indwelling urinary catheter, followed by eventual spontaneous closure. More recently, it has been found that fibrin occlusion therapy may also be a choice of therapy for VVFs, if available (Spurlock, 2011 and Schorge, 2008).
Surgical therapy is another choice of therapy for treatment of a VVF, and is associated with cure rates of 90% for uncomplicated cases (UNFPA, 2011). It can be done via a variety of approaches including transvaginal, Latzko technique, classical technique, transperitoneal, or laparascopic (Schorge, 2008). The cost of fistula treatment, including surgery, hospital care, and rehabilitation, has been estimated at US$300 in low-resourced settings (UNFPA, 2011).
A 2012 project, globalfistulamap.org, identifies sites worldwide where surgery might be available.
Medical therapy for a RVF involves drainage of abscesses and directed antibiotic treatment, with hopeful eventual spontaneous closure. Additionally, dietary modification with increased fiber may help control symptoms. Surgical therapy in the treatment of choice for persisting RVFs, although it is often difficult to surgically treat RVFs caused by radiation (Taylor, 2011).
Counselling and support should also be provided for women who have suffered with fistula for some time.
Consequences and Course
Unrepaired fistulas are catastrophic for women, who are often treated as outcasts due to the smell of draining urine or feces. A woman's husband will often abandon her because of this. Nerve damage, infection and kidney failure may also follow the trauma leading to vaginal fistula.
Surgical repair of vaginal fistulas is standard of care for nonhealing fistula, but also comes with a risk of bleeding, infection, adhesions, and possible damage to other tissues (Spurlock, 2011, and Taylor, 2011).
Resources and References
EndFistula.com - Site of the United Nations Population Fund (UNFPA).
Mayo Foundation for Medical Education and Research. "Vaginal Fistulas." Mayo Clinic. 2001-2011. Web. 10 July 2011.
Spurlock, John, MD. "Vesicovaginal Fistula." Emedicine. 1994-2011. Web. 10 July 2011.
Taylor, Dana, MD, FACS. "Rectovaginal Fistula." Emedicine. 1994-2011. Web. 10 July 2011.
Schorge, John O, et al. "Genitourinary Fistulas." Williams Gynecology. The McGraw-Hill Companies, Inc, 2008. Access Medicine. Web. 10 July 2011.
FistulaCare: Fistula Orientation for Health Workers
Topic Development
authors: Marissa Vance, 2011
reviewers: Dr Dan Reilly, 2011
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