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 fistula 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.
Anal fistula 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 fistula 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.
Kshara Sutra is utilized in the treatment of fistula in Ayurveda. Kshara Sutra is a seton thread medicated with organic alkalis,such as Apamargakshara(Achyranthesaspera), Arkakshara(Caltropisgigantea) or Snuhikshara (Euphorbia lingularia). The alkali is repeatedly coated on the seton thread 15 – 21 times. Apart from this, natural antibiotic like haridra powder, guggulu, etc are also used to make Ksharasutra. The mechanical action of the threads and the chemical action of the drugs coated , collectively do the work of cutting, curetting, draining, and cleaning the fistulous track, thus promoting healing of the track/ wound. This also acts both as the antiseptic and fibrotic agent to induce healing. The process of healing starts from deeper tissues and moves towards the periphery. This can be applied and changed periodically till the thread cuts the fistulous tract. Since the sphincter heals by fibrosis, there is no incontinence.
Under local anaesthesia, the kshara sutra is inserted into the tract and the two ends of the thread are tied forming a loop. The alkalis coated on the thread are continuously released throughout the length of the track there by cutting, curetting, draining cleansing and healing the track. This therapeutic action of the thread lasts for seven days. The old thread is then replaced with a new thread following the same procedure. Depending on the length of the tract and the extent of damage, the kshara sutra may be changed up to 5 times. The changing of the thread is a simple procedure taking about 1 to 2 minutes and requires no anaesthesia.
The procedure does not require hospitalization for more than 4 to 5 hours.
The patient requires minimal bed rest and can resume daily activities within 12 – 24 hours
No painful dressings required
The drugs coated on the Kshar-Sutra are slowly and gradually released into the track and the wound, leaving no abscess overseen. These abscess are drained out by the action of the drugs.
The sphincteric muscles are not dissected and hence the possibility of incontinence is ruled out.
The reoccurrence rate of fistula treated with kshara sutra ligation procedure is less than 2%. This is because the medicines on the thread gradually and continually curate the payogenic membrane and fibrous tissue in the track and thus leave no pus pockets undrained. In some cases, the fistula can reoccur despite having surgery. After having a fistulotomy, the reoccurrence rate rises to 21%. After an advancement flap procedure, the reoccurrence rate may be as high as 36%.