Rectovaginal Fistula

• • Passing stool and flatus through the vagina

  • Communication between the anterior wall of the rectum and posterior wall of the vagina

  • Tract generally visible or palpable

  • Etiologies include:

  • -Obstetric injury

    -Crohn disease

    -Diverticulitis

    -Radiation

    -Undrained cryptoglandular disease

    -Foreign body trauma

    -Surgical extirpation of anterior rectal tumors

    -Malignancies of the rectum, cervix, or vagina

  • Classified as low, middle, or high

  • Considered low if can be repaired from a perineal approach

  • Considered high if must be repaired transabdominally

Epidemiology

• • Obstetric injury accounts for the majority of rectovaginal fistulae

Symptoms and Signs

• • Passing stool and flatus through the vagina is characteristic

  • There may be varying degrees of incontinence

  • With low or small fistula, passage of flatus through vagina most common complaint

  • Large fistula

  • -Vaginal discharge with fecal odor

    -Passage of flatus and stool per vagina

    -Vaginitis

  • An opening in the vagina or rectum may be seen or felt on physical exam

  • Anoscopy may detect opening in anal canal

Laboratory Findings

• • No specific findings

Imaging Findings

• • A vaginogram or barium enema may identify the fistula

  • If the fistula is not demonstrated on radiographic or physical exam, a dilute methylene blue enema may be administered with a tampon in the vagina

  • -If a fistula is present, it should be confirmed by methylene blue staining of the tampon

  • Proctoscopy may be required to visualize opening in mid to high fistula

• • The signs and symptoms of a rectovaginal fistula are fairly unmistakable

  • -The important differential is the cause of the fistula, as this affects management

• • Complete history and physical exam

  • History of obstetric trauma, foreign body, inflammatory bowel disease, radiation injury

  • Bimanual exam

  • Methylene blue enema

  • Anoscopy or proctoscopy

When to Admit

• • Signs of perineal sepsis

• • The cause and location of the fistula determine the treatment

  • -Involvement of surrounding tissue by the disease process that leads to the fistula may limit the surgical options

  • Inciting event (injury, inflammation, radiation injury) should be allowed to heal or subside prior to undertaking repair

  • About 50% of small rectovaginal fistulae secondary to obstetric trauma heal spontaneously

  • Fistulas secondary to cryptoglandular disease may close spontaneously once the primary process is drained

  • Fistulas secondary to Crohn disease rarely heal spontaneously

  • -Require aggressive medical therapy

    -Once in remission, local advancement flap procedures may be performed

  • Temporary diverting colostomy may be necessary in patients with severe disease or complex rectovaginal fistulae that do not respond to local measures

Surgery

Indications

• • Fistulas secondary to radiation injury are not amenable to local procedures

  • -Transabdominal resection and coloanal anastomosis is ...