Urinary Fistula Background Information
What is a fistula?
Fistula is an abnormal connection between two different parts of the body. It is like a tube or a tunnel that connects these two structures. This leads to mixing of the contents of these two structures. For instance, a fistula between the urethra and the rectum would lead to urine getting into the rectum while stool gets into the urethra. Urinary fistulas usually involve a connection between the bladder, prostate or urethra, and the colon, rectum, vagina or skin. One rare but serious fistula is between the bladder/prostate/urethra and the
What are the types of urinary fistula and what causes each of them?
A vesicovaginal fistula is a fistula between the bladder and the vagina. The most common cause of this in developed countries is hysterectomy (surgery to remove the uterus). The most common cause in developing countries is obstructed labor (when the baby gets stuck in the birth canal).
A colovesical fistula is a fistula between the colon and the bladder. The most common cause of this is diverticulitis, an infection of the colon that leads to the colon perforating and boring a hole into the bladder.
Rectoprostatic or rectourethral
A rectoprostatic or rectourethral fistula is a fistula between the rectum and the prostate or urethra and occurs only in men. The cause is usually prostate cancer radiation or surgery.
A ureterovaginal fistula is a fistula between the ureter (tube that carries urine from the kidney to the bladder) and the vagina. The most common cause of this is hysterectomy.
A urethrocutaneous fistula is a fistula between the urethra and the skin in a man. This usually occurs on the shaft of the penis and the most common cause is previous hypospadias repair. Hypospadias is an abnormal development of the urethra at birth. Surgery to correct hypospadias has very high success rates. In just 1 or 2% of boys or men who have undergone this surgery, a fistula can develop.
Pubo-urethral, a.k.a. Pubo-prostatic, a.k.a. Pubo-vesical, a.k.a. Pubo-urethral, a.k.a. Uro-pubic
These are all essentially the sameas each other. There is a fistula from the bladder/prostate/urethra to the pubic bone. The most common cause is radiation combined with repeated treatment of a scar tissue in the urethra or prostate. When dilating or cutting that scar tissue, a crack is made in the lining of the urethra. Due to the radiation, that crack does not heal well and the urine leaks through the crack until it connects with the pubic bone. This often causes significant pain in the pubic bone and inner thigh or groin area, especially with walking. This is a very serious condition and requires surgical treatment to stop the infection. Antibiotics alone cannot control the infection.
What does it feel like to have a fistula?
That depends on the type of fistula. A fistula between the bladder and the vagina in a woman or between the urethra and the skin of the penis in a man will lead to urinary leakage (incontinence). A fistula between the colon and bladder or between the rectum and prostate causes mixing of the urine and feces; this can lead to urinary tract infections and watery stools. A fistula between the urinary tract and the pubic bone leads to pain in the pubic area, especially with walking.
How common is a urinary fistula?
Urinary fistulas are uncommon. The most common types of urinary fistulas, although still rare, are vesicovaginal fistula and colovesical fistula. Fistulas as a result of prostate cancer treatment occur in less than 1% of all men treatefd for prostate cancer.
How do I find out if I have a fistula?
If you have some of the symptoms and risk factors listed above, then you should see your primary care provider or a urologist. They may check your urine for infection. Once they rule out the more common causes of your symptoms, like a bladder infection, they may recommend evaluation for a fistula. Evaluation would usually include an x-ray and a cystoscopy. The type of x-ray depends on the type of fistula we suspect; it could be a CT scan or a dedicated x-ray of the urethra or bladder. A cystoscopy is a camera exam of the urethra and bladder. A pubourethral fistula is best seen with an MRI.
What are the treatments options for urinary fistula?
Catheter drainage and patience
Some fistulas will close on their own if the bladder is kept empty with a catheter for several weeks. This is most likely to be successful in fistulas caused by a recent surgery – a prime example is vesicovaginal fistula after hysterectomy. This is unlikely to be successful in fistulas caused by radiation or infection.
Very small fistulas will sometimes close by cauterizing them. This is most likely to be successful in fistula is caused by a recent surgery – a prime example is vesicovaginal fistula after hysterectomy. This is unlikely to be successful in large fistulas or those caused by radiation or infection. The doctor places a camera (scope) into the bladder and, after locating the site of the fistula, they pass a small probe through the scope and use it to cauterize the surface of the fistula. When the body heals from the irritation of the cauterization there is a chance that it will heal the fistula closed.
Most fistulas will only heal with surgery. While some fistulas are easier to repair than others, there is a common premise to how these surgeries are done regardless of the type of fistula. The fistula tunnel connecting the two structures is removed and then the resulting holes in the two structures are both closed. Finally, some healthy tissue, like muscle, is placed in between the two closed holes to prevent the fistula from reoccurring. In severe cases, one or both of the structures involved in the fistula must be removed too because they are too damaged to be repaired. An example would be in a pubo-urethral fistula after radiation where some pubic bone and/or the bladder is removed in order to control the infection.