A fistula is an abnormal communication or passageway between two epithelial surfaces, meaning between the surfaces of our body. In human anatomy, a fistula typically refers to an abnormal connection between two hollow spaces that normally do not communicate, such as the gastrointestinal tract, respiratory tract, or urinary tract. Fistulas can also occur between solid organs, such as the bladder and skin.
Fistulas are formed due to sores and ulcers inside internal organs or body walls. This is mainly due to chronic conditions leading to an inflammatory response in the body. Although fistulas can occur anywhere in the body, they are most common in the lower gastrointestinal tract. When fistulas form in this part of the body, they are often associated with Crohn’s disease and other inflammatory bowel disorders.
The most common type of fistula is a fistula-in-ano, which is an abnormal connection between the rectum and anus. Other kinds of fistulas include those involving the bladder, intestine, kidney, or urethra. Fistulas can also occur in the blood vessels, cartilage, joint capsules, lymph nodes, skin, or tendons.
Signs and Symptoms
The fistula presents as a discharging sinus, most commonly around the anus or the area from where we pass stool. This is the commonest type of fistula that we see, and we call it an anal fistula.
The fistula can be categorized into high and low types depending on communication with the sphincter controlling muscle. Hence, it is important to diagnose the anal fistula using a test called MRI pelvis, where we give the medicine through the vein and take multiple films to see the fistula tract going above the muscle or below.
Treatment of fistula is surgery and in today’s era, it can be done through a minimally invasive approach using laser fiber.
The commonest fistulas are low types, which can be managed alone with laser as they do not cross the muscle sphincter and have a good prognosis.
Multiple treatment options for high fistula are available, including laser with open surgery as well as placement of a thread called seton and serially tightening it.
Another procedure that has recently gained popularity is VAAFT (video-assisted anal fistula treatment).