Rectovaginal fistula

Diagnosis

The diagnosis of a rectovaginal fistula often starts with a physical exam, pelvic exam, review of medical history and discussing the symptoms. The doctor may require several tests to confirm the diagnosis.

Physical examination: During a physical exam, the doctor will examine the vagina, anus, and perineum. The vagina may be inspect using a medical tool known as a speculum. The speculum will be inserted gently to inspect vagina. This allows the doctor to perform a more thorough exam. In almost similar way, the proctoscope can help the doctor view the anus and rectum easily.

Physical exam is done to find the rectovaginal fistula and evaluate for any potential tumor masses, infections, or abscesses.  During the procedure, the doctor may extract a tissue sample for laboratory analysis (biopsy).

Tests for identifying fistulas: There can be instances that a rectovaginal fistula cannot be found or assessed during a physical examination. The doctor may require different tests for accurate diagnosis. These tests might already be a part of the initial preparations for a surgery.

• Computerized tomography (CT) scan: A CT scan is often used to determine the cause and location of a fistula. Compared to a typical X-ray, a CT scan offers more detailed information.
• Magnetic resonance imaging (MRI): This is a noninvasive procedure that uses magnetic and radio waves which provide images of the pelvic organs and tissues. A precise description of the position of the fistula, the involvement of other pelvic organs, and the presence of tumors can all be seen on an MRI.
• Contrast tests: A contrast substance or dye is used to make the bowel or vagina visible on an X-ray image, usually during a vaginogram or a barium enema exam. An upper rectum fistula can be discovered through this method.
• Anorectal ultrasound. An ultrasound produces a picture of the interior of the pelvis using sound waves. This examination may reveal birth-related damage and assess the anal sphincter’s structural strength. An apparatus resembling a wand is placed into the anus and rectum during this test.
• Blue dye test: Also known as methylene enema. This is a 15 to 20-minute procedure wherein the vagina is inserted with a tampon, then the rectum is injected with a blue dye. If the tampon turns blue, it indicates a fistula.
• Anorectal manometry: Although this test cannot find fistulas, it may be useful in creating an effective treatment plan or fistula repair. It evaluates how well the rectum and rectal sphincter functions and regulate stool flow.
• Other tests: The doctor might request a flexible sigmoidoscopy or a colonoscopy to examine your colon and rectum for presence of other diseases such as IBD. To assist in the diagnosis of Crohn’s disease, the doctor may perform a biopsy during the operation to obtain small samples of tissue for laboratory testing.

Treatment

The treatment will focus on closing the unusual hole between the vagina and rectum. The treatment plan is developed based on the cause, size, location of the fistula, and its impact on the surrounding tissues. It typically involves medications and surgery.

• Medications: Medications may be prescribed as a treatment or a surgery preparation:
  • Antibiotics: For patients with Crohn’s disease who form a fistula, antibiotics may be advised. But it generally prescribed to all patients before surgery to lower the risk of infection particularly in the region where the fistula is.
  • Infliximab: This is a prescribed injectable solution that can treat women with Crohn’s disease by reducing inflammation and repairing fistulas.
• Surgery: Surgical treatment is often recommended to treat a rectovaginal fistula. However, surgery may be postponed if the patient has an infection or inflammation within the area. The fistula’s surrounding tissues must heal first. The doctor may advise waiting three to six months while the infection is solved.

Surgery to repair a rectovaginal fistula can be performed through the abdominal, vagina, or perineum. The objective is to cut out the fistula tract and seal the hole with healthy tissue. A gynecologic surgeon, a colorectal surgeon, or both working jointly may perform surgery to seal a fistula.

Common surgical treatments include:

• • Sewing a biologic tissue plug or patch into the anal fistula: to allow the tissue to repair the fistula and grow into the patch.
  • Applying a tissue graft: from another part of the body or covering the fistula opening with a flap of healthy tissue.
  • Repairing the anal sphincter muscles: if the fistula, scarring, radiation, or Crohn’s disease have caused tissue damage.
  • Performing a colostomy before repairing a fistula in complex or recurrent cases: may be recommend for some women especially those with tissue damage or scarring from prior surgery or radiation treatment, a persistent infection or substantial fecal contamination, a malignant tumor, or an abscess. A stoma or an opening in the abdominal wall is created during the surgery. This will channel the stool through an opening in the belly rather than through the rectum. Until the fistula heals, waste is collected in a bag. Later, another procedure will be required to close the stoma and reattach the intestine. The normal bowel function is restored three to six months after the fistula is declared healed. A colostomy is rarely necessary, and the doctor might hold off on fixing the fistula for eight to 12 weeks if a colostomy is required.