Anovaginal fistulae

Anovaginal fistulae are an uncommon type of anal fistulous disease. The symptoms can be minimal but frequently are disabling. Obstetric injury is the most common cause, but many other disease states can produce this communication. It is important to completely evaluate the patient before any consideration is given to surgical correction. This includes evaluation of the function of the anal sphincter, involvement of any other organ systems, and tissue diagnosis if the cause is uncertain. It is also important to delay surgical correction until any inflammation and infection have subsided. Many different surgical procedures have been reported in the literature for repair of these fistulae, most with success rates of at least 75%. It is important to remember the physiologic high-pressure zone in the anal canal when planning surgical correction. Fistulae secondary to inflammatory bowel disease have a markedly reduced success rate, and the presence of anal Crohn's disease should be suspected, especially when a previous surgical repair has failed. Medical management should be used either to heal the fistula nonoperatively or to improve the surgical result. Finally, some fistulae secondary to neoplasia, radiation, anastomotic leaks, or inflammatory bowel disease require diversion of the fecal stream either as an adjunct to repair or as definitive treatment. Proper preoperative evaluation of the patient and selection of the operation provide the optimum result.