WHAT IS AN ANAL FISTULA? Anal fistula, or fistula-in-ano, is an abnormal connection or channel like structure, between the surface of the anal canal and the exterior perianal skin.
Anal fistulae originate from the anal glands, which are located between the two layers of the anal sphincters and which drain into the anal canal. If the outlet of these glands becomes blocked, an abscess can form which can eventually point to the skin surface. The tract formed by this process is the fistula.
Ancient Ayurveda surgeon, Susruta has described five types of Bhagandara(Sataponak, Ustragriwa, Parisrabi, Sambukawarta, Unmargi). They have been classified according to the vitiation of the three doshas and the shape & site of the fistula tract.
CAUSES OF FISTULA?
Anal fistulas commonly occur due to an anal abscess.
An abscess is a collection of pus and infected fluid. An anal abscess usually develops after a small gland, just inside the anus, becomes infected with bacteria.
A fistula may occur if an abscess has not completely healed, or if the infected fluid has not been entirely drained away.
An anal fistula may also develop as a result of:
a growth or ulcer (painful sore)
a complication from surgery
a congenital abnormality (a health problem that you were born with)
Anal fistulae are also a common complication of conditions that result in inflammation of the intestines. Some of these conditions include:
Irritable bowel syndrome (IBS): a chronic (long-term) disorder that affects the digestive system, causing abdominal pain, diarrhoea and constipation.
Diverticulitis: the formation of small pouches that stick out of the side of the large intestine (colon), which become infected and inflamed.
Ulcerative colitis: a chronic condition that causes the colon to become inflamed and can cause ulcers to form on the lining of the colon.
Crohn’s disease: a chronic condition that causes inflammation of the lining of the digestive system.
SYMPTOMS OF FISTULA
Anal fistulae can present with many different symptoms such as:
Discharge – either bloody or purulent
Pruritus ani– itching around the anus
Systemic symptoms if abscess becomes infected
DIAGNOSIS OF FISTULA
Diagnosis is by examination, either in an outpatient setting or under anaesthesia. The examination can be an Anoscopy.
The opening of the fistula onto the skin may be seen
The area may be painful on examination
There may be redness
A discharge may be seen
It may be possible to explore the fistula using a fistula probe (a narrow instrument) and in this way it may be possible to find both openings of the fistula