A urethral fistula is a connection between the urethra and the vagina.
Around the world, fistula is most commonly caused during childbirth with prolonged labor and compression of the urethral during childbirth. This cause is uncommon, however, in the United States where patients have better access to medical care and c-section rates are higher.
More commonly, in the developed world, a fistula is caused either by trauma from medical procedures, radiation therapy, or an untreated infection from a urethral diverticulum.
The fistula can be diagnosed either on physical exam if it is large. In this case the hole can be palpated in the urethra on evaluation of the vagina. Other ways of confirming the fistula include a cystoscopy where a scope is inserted into the bladder to look at the urethra or with a dye study called a voiding cystouethrogram where dye is placed in the bladder and the patient asked to urinate while x-rays are being taken.
Typically the fistula can only be fixed surgically but occasionally very small fistulas may be able to close spontaneously with catheter drainage but this is unusual.
Generally, the surgery is an outpatient surgery and the hole is closed in multiple layers and the catheters left In for a few weeks while the tissue heals.
It depends a little on the complexity of the fistula but generally it can be fixed with high success rates.