In medicine, a fistula
(pl. fistulas or fistulae) is an abnormal connection or passageway between two epithelium
-lined organs or vessels that normally do not connect.
Location of fistulas
Fistulas can develop in various parts of the body. The following list is sorted by the International Statistical Classification of Diseases and Related Health Problems
H: Diseases of the eye, adnexa, ear, and mastoid process
I: Diseases of the circulatory system
J: Diseases of the respiratory system
K: Diseases of the digestive system
M: Diseases of the musculoskeletal system and connective tissue
N: Diseases of the genitourinary system
Q: Congenital malformations, deformations and chromosomal abnormalities
T: External causes
Types of fistulas
Various types of fistulas include:
- Blind: with only one open end
- Complete: with both external and internal openings
- Incomplete: a fistula with an external skin opening, which does not connect to any internal organ
Although most fistulas are in forms of a tube, some can also have multiple branches.
Various causes of fistula are:
- Diseases: Inflammatory bowel diseases, such as Crohn's disease and ulcerative colitis, are the leading causes of anorectal, enteroenteral, and enterocutaneous fistulas. A person with severe stage-3 hidradenitis suppurativa will also develop fistulas.
- Medical treatment: Complications from gallbladder surgery can lead to biliary fistula. Radiation therapy can lead to vesicovaginal fistula. An arteriovenous fistula can be deliberately created, as described below in therapeutic use.
- Trauma: Head trauma can lead to perilymph fistulas, whereas trauma to other parts of the body can cause arteriovenous fistulas. Obstructed labor can lead to vesicovaginal and rectovaginal fistulas. An obstetric fistula develops when blood supply to the tissues of the vagina and the bladder (and/or rectum) is cut off during prolonged obstructed labor. The tissues die and a hole forms through which urine and/or feces pass uncontrollably. Vesicovaginal and rectovaginal fistulas may also be caused by rape, in particular gang rape, and rape with foreign objects, as evidenced by the abnormally high number of women in conflict areas who have suffered fistulae. In 2003, thousands of women in eastern Congo presented themselves for treatment of traumatic fistula caused by systematic, violent gang rape that occurred during the country's five years of war. So many cases have been reported that the destruction of the vagina is considered a war injury and recorded by doctors as a crime of combat.
Treatment for fistulae varies depending on the cause and extent of the fistula, but often involves surgical intervention combined with antibiotic therapy.
Typically the first step in treating a fistula is an examination by a doctor to determine the extent and "path" that the fistula takes through the tissue.
In some cases the fistula is temporarily covered, for example a fistula caused by cleft palate is often treated with a palatal obturator to delay the need for surgery to a more appropriate age.
Surgery is often required to assure adequate drainage of the fistula (so that pus may escape without forming an abscess). Various surgical procedures are commonly used, most commonly fistulotomy, placement of a seton (a cord that is passed through the path of the fistula to keep it open for draining), or an endorectal flap procedure (where healthy tissue is pulled over the internal side of the fistula to keep feces or other material from reinfecting the channel). Treatments involving filling the fistula with fibrin glue or plugging it with plugs made of porcine small intestine submucosa have also been explored in recent years, with variable success. Surgery for anorectal fistulae is not without side effects, including recurrence, reinfection, and incontinence.
It is important to note that surgical treatment of a fistula without diagnosis or management of the underlying condition, if any, is not recommended. For example, surgical treatment of fistulae in Crohn's disease can be effective, but if the Crohn's disease itself is not treated, the rate of recurrence of fistula is very high (well above 50%).
In end stage renal failure patients, a cimino fistula is often deliberately created in the arm by means of a short day surgery in order to permit easier withdrawal of blood for hemodialysis.
As a radical treatment for portal hypertension, surgical creation of a portacaval fistula produces an anastomosis between the hepatic portal vein and the inferior vena cava across the omental foramen (of Winslow). This spares the portal venous system from high pressure which can cause esophageal varices, caput madusae, and hemorrhoids.