What Are the Causes of Fistula?

When the term "fistula" is used, it typically refers to abnormal connection between organs, body cavities, blood vessels or the skin. There are several types of fistulas that can result in the human body including a rectovaginal fistula, or an opening between the vagina and rectum, arteriovenous, or a connection between an artery and a vein, gastric, which causes and opening from the stomach to the skin and metroperitoneal, or an opening between the peritoneal cavity and the uterus. This condition is very serious and can produce numerous symptoms depending on the type and location of the fistula. The vast majority of fistulas require surgical repair. But it's important to understand what causes this unfortunate condition in the first place so proper treatment steps can be taken.

Childbirth

The occurrence of rectovaginal fistulas is rare, but the most common reason they develop is from an injury during childbirth. The perineum might tear or an episiotomy might tear more than was intended. This happens in only a small portion of births and usually only appears after a very difficult labor.

Surgery

Some surgical procedures can unintentionally create a fistula between the vagina and the rectum, the bladder and the vagina, arteries and veins and even the stomach and the skin. All surgery is traumatic, and some incisions may not heal properly, leaving holes joining organs, intestines or even blood vessels.

Crohn's Disease

Crohn's disease is another potential cause of fistulas. Since this disease causes the bowel to become inflamed, it can lead to a weak spot in the wall. This weak spot could result in a fistula between the rectum and the vagina or within the intestines themselves, requiring surgical repair. However, any inflammatory disease has the potential to cause a fistula in numerous parts of the body.

Infection

Infection is another cause of a fistula. Infections can lead to tissue death when left untreated. It is plausible that the presence of bacteria or fungi can wear away tissue, leaving one organ exposed to another organ. Areas that are especially susceptible to fistulas caused by infection include the rectum, vagina, intestines, neck and sinuses.

Cancer

Developing cancer in any part of the body can cause a fistula. Tumors can lead to a breakdown of the tissue between organs and other structures. Radiation treatment can weaken the tissue between the two areas, causing a fistula to develop later. For example, if you were diagnosed with uterine cancer, treatment or surgery in this area could cause a fistula to develop between the uterus and the peritoneal cavity. Usually, a fistula caused by radiation treatment will appear within two years following treatment.