Rectovaginal Fistula - Symptoms, Causes and Treatment

The rectovaginal fistulas are of 2 types which are simple rectovaginal fistula and complex rectovaginal fistula. 

1. Simple Rectovaginal Fistulas are smaller in diameter and lower in location. These occur due to infection and injury.
2. Complex Rectovaginal Fistulas are larger in diameter and higher in location. These mainly occur due to cancer, inflammatory bowel diseases, irradiation, and large bowel diverticulosis.

The signs and symptoms of rectovaginal fistula are:

1. The passage of stool, pus, or gas through the vagina.
2. Pain during sexual intercourse 
3. Problem controlling the release of faeces called faecal incontinence 
4. Foul-smelling discharge from the vaginal opening
5. Diarrhoea, Nausea, and vomiting 
6. Vaginal and Rectal bleeding 
7. Darkening of the vaginal area
8. Pain in the pelvic area
9. Irritation in your vagina, vulva, and perineum (area between anus and vagina)
10. Unexplained weight loss
11. Recurrent vaginal(Vaginitis) and urinary tract infections

The various causes of rectovaginal fistula are:

1. Injuries during childbirth: Injuries due to child deliveries are the most common cause of the rectovaginal fistula. It occurs due to prolonged and challenging labour that leads to vaginal tearing. It can also lead to injury to the anal sphincter and the rings of muscles that hold the stool. 
2. Inflammatory bowel disease (IBD): IBD is one of the common causes of rectovaginal fistula. Inflammatory bowel diseases, like Crohn's disease and ulcerative colitis, cause digestive tract inflammation. Therefore, they increase the risk of developing a fistula.
3. Cancer: Cancer in the pelvic area, such as cervical cancer, vaginal cancer, or colorectal cancer, can cause a rectovaginal fistula. 
4. Radiation therapy to the pelvis: Radiation therapy of the pelvic region also increases the risk of fistula. It usually develops after six months to two years of treatment.
5. Surgeries of the pelvic area: The surgery of the pelvic region, along with hysterectomy and Caesarean, causes infection and injury leading to fistula formation. 
6. Other causes: The other possible causes of rectovaginal fistula includes infection of the anus and rectum, infections due to AIDS, long-term inflammation of the colon and rectum, or infected pouches in the digestive tract (diverticulitis)

The risks factors of rectovaginal fistula are:

1. Multiple vaginal deliveries 
2. Prolonged and difficult labour
3. Cancer of the vagina, rectum, cervix, or anus and radiation therapy to treat the cancer
4. Ulcerative colitis or Crohn's disease 
5. If the vagina is ripped or cut with an episiotomy during labour
6. Surgery for uterus removal called hysterectomy or surgery of the pelvic area
7. Infection or abscess

There is no method that can entirely prevent the occurrence of rectovaginal fistula. However, some of the measures that can be taken for the prevention and healing of the fistula:

1. Eat a balanced healthy diet rich in proteins and fibre.
2. Maintain good hygiene and cleanliness of the pubic area to prevent bacterial infections.
3. Avoid unhealthy lifestyles and stop smoking and drinking.

The following tests are carried out for the diagnosis of rectovaginal fistula:

1. Physical examination: The doctor performs a physical exam to locate the fistula and check for possible infection, inflammation, tumour, or abscess. The healthcare provider may also insert a speculum in the vagina using the gloved hand. 
2. Contrast test: This test identifies a fistula present in the upper rectum. In this test, a contrast material is used as a medium. It shows the vagina and bowel image on an X-ray.
3. Computerized tomography (CT) scan: CT scan is a diagnostic technique that provides detailed images of the abdomen and pelvis. It is carried out to locate the position and cause of the fistula.
4. Magnetic Resonance Imaging (MRI): It is a diagnostic technique that uses magnetic waves to produce images of soft tissue. It shows the location of the fistula.
5. Anorectal ultrasound: This diagnostic test uses sound waves to produce a detailed image of the anus, rectum, and vagina. This test evaluates the structure of the internal organs.
6. Blue Dye test: In this test, a tampon is inserted into the vagina, and then blue dye is injected into the rectum. The blue stain on the tampon indicates the presence of a fistula.

The treatment of a rectovaginal fistula depends on the cause of the fistula, the severity of the symptoms, the location of the fistula, the person's health, the size of the fistula, and the effect on the surrounding tissue. 

1. Medications: The small fistula heals over time. The doctor will prescribe the medicines to treat the fistula. The doctor will prescribe antibiotics for infection and Infliximab to reduce the inflammation in Crohn's disease.
2. Surgical method: This surgery is done to close the hole and repair a rectovaginal fistula. The surgical options involve the following procedures such as:
   1. Sewing of the fistula opening: In this technique, the surgeon sews the fistula to close the gap. The surgeon may use the patch of the biological tissue or lab-made tissue in the fistula to repair it. The tissue grows over the patch and closes the hole that heals over time.
   2. Tissue Grafting: In this, a surgeon takes a part of nearby tissue and applies it on the fistula or applies a flap of healthy tissue over the fistula opening.
   3. Colostomy: In this procedure, the stool is diverted away from the large intestine and rectum through the abdomen until the fistula heals. The surgical opening through the abdomen is called a stoma, through which stool leaves the body. Once the fistula heals, another surgery is carried out later to reconnect the intestine and rectum, closing the stoma.
   4. Repairing the anal sphincter muscles: In this method, the anal sphincter muscles are repaired through surgery if they are damaged through the fistula.

Rectovaginal fistula surgery is a safe and effective procedure. A team of skilled surgeons performs the surgery. However, some of the complications associated with the surgery are:

1. Vaginal Bleeding 
2. Infection at the site of surgery
3. The formation of abscesses at the fistula site can lead to life-threatening conditions if not treated.
4. Stool leakage even after the surgery
5. Recurrent fistula formation
6. Inflammation and irritation in the vagina and skin around the anus
7. Pain and vaginal spasmsspams
8. Urinary tract infection