bubble_chart Overview

Clinically, bladder fistulas are relatively common and can communicate with the skin, intestines, or female reproductive organs. The primary disease is often a condition outside the urinary system. Common causes include: ① Primary intestinal diseases—diverticulitis accounts for 50–60%; colorectal cancer 20–25%, and Crohn’s disease 10%; ② Primary gynecological conditions—pressure necrosis caused by difficult delivery, advanced cervical carcinoma; ③ Post-hysterectomy, low-segment cesarean section, or post-radiotherapy for tumors; ④ Injury. Necrotic erosion of malignant tumors in the colon, small intestine, vagina, or cervix, or grade III bladder injury leading to perivesical abscess formation, may rupture into the perineum or abdominal cavity. Bladder injury may also occur accidentally during gynecological or vaginal surgeries. Additionally, persistent fistula formation can result from cystolithotomy or post-prostatectomy.

bubble_chart Clinical Manifestations

(1) Bladder-intestinal fistula: Symptoms such as bladder irritation, fecal fistula disease, and gas discharge from the urethra may occur, often accompanied by changes in bowel habits caused by the primary intestinal disease. Physical examination may reveal signs of intestinal obstruction. If caused by inflammatory diseases, abdominal muscle tension may be observed. Urine tests often indicate concurrent infection.

Barium enema and sigmoidoscopy can reveal the presence of the fistula. Generally, after a barium enema, centrifuging a urine sample and performing an X-ray examination can confirm the presence of a bladder-colonic fistula if radiopaque barium is detected. Cystoscopy has significant diagnostic value, aiding in locating the fistula tract. Under the scope, the bladder wall may show obvious inflammatory changes. Catheterization and contrast injection through the fistula often help confirm the diagnosis.

(2) Bladder-vaginal fistula: This is relatively common and often secondary to obstetric, surgical, or radiation therapy injuries or cervical carcinoma. During cystoscopy, catheter insertion through the fistula opening can directly connect to the vagina. Vaginal contrast imaging often clearly displays ureterovaginal, bladder-vaginal, and rectovaginal fistulas. Alternatively, inserting a Foley catheter through the vagina, inflating the balloon, and injecting an appropriate amount of contrast agent can also aid in diagnosis. In some cases, cancerous changes may appear at the edges of the fistula. Persky (1980) reported six cases of bladder-vaginal fistula in children, all of which were complications of surgical injuries.

(3) Bladder-appendage fistula: This rare type of bladder fistula can be diagnosed through vaginal examination and identified via cystoscopy to locate the fistula opening.

bubble_chart Treatment Measures

(1) Bladder-intestinal fistula: If the lesion is located in the rectum or sigmoid colon, a proximal colostomy can be performed first. After the inflammation subsides, the affected intestinal segment is resected and the fistula is closed, followed by closure of the colostomy. Some scholars suggest that the entire procedure should be completed in the initial stage [first stage]. For small intestine or appendix-bladder fistulas, partial intestinal resection or appendectomy is required, along with closure of the bladder fistula.

(2) Bladder-vaginal fistula: Smaller bladder-vaginal fistulas can be treated with electrocautery, with postoperative indwelling catheterization for at least 2 weeks. Aycinena (1977) reported that for some small bladder-vaginal fistulas, curettage of the vaginal fistula opening with a metal curette can promote closure, followed by 3 weeks of indwelling catheterization, yielding good results.

Larger bladder-vaginal fistulas secondary to obstetric or surgical injuries can be surgically repaired via the vaginal or bladder approach. Fistulas caused by radiotherapy for cervical carcinoma are more difficult to repair due to poor local tissue vascularity. For bladder-vaginal fistulas caused by direct invasion of the bladder by cervical carcinoma, surgical repair is impossible, and urinary diversion (e.g., ureterosigmoidostomy) is often required for the upper urinary tract.

(3) Bladder-adnexal fistula: This can be cured by resection of the involved female reproductive organs and closure of the bladder fistula.

bubble_chart Prognosis

The surgical repair success rate for bladder fistulas caused by benign diseases or surgical trauma is very high. However, the prognosis is often poor due to tissue necrosis caused by radiotherapy. Managing fistulas secondary to invasive cancer is more challenging.

bubble_chart Differentiation

Clinically, it is important to differentiate between bladder-vaginal fistula and ureter-vaginal fistula.

Oral administration of pyridium turns the urine orange-yellow. One hour later, three cotton balls are placed in the vagina, and methylene blue is injected into the bladder. The patient is instructed to walk briefly before the cotton balls are examined. If the outermost cotton ball is stained orange-yellow, it suggests a ureter-vaginal fistula. If the innermost cotton ball is stained blue, a bladder-vaginal fistula can be diagnosed. If only the outermost cotton ball appears blue, the patient may have urinary incontinence.