•           Fistula-in-ano is a tract lined by granulation that connects superficially the skin around the anus and deeply the anal canal or the rectum.

•           Low level fistula opens into the anal canal below the anorectal ring.

•           The high-level fistula opens into the canal at or above the anorectal ring.

•           It is important to know the level of fistula since a low-level fistula can be laid open without fear of incontinence.

Salient features

•           Persistent seropurulent discharge that may be blood stained.

•           Pain and sometimes a history of a perianal abscess that has been drained.

•           Fistula-in-ano maybe associated with tuberculosis, Crohn's disease, carcinoma, bilharziasis.

•           There is usually an opening within 3-4 cm of the anal orifice with granulation tissue. The fistula heals only to recur later on.

•           Digital examination may reveal the internal opening.

Treatment

A.  Nonpharmacological

Local hygiene and sitz bath. Diet modification to avoid constipation.

B.  Pharmacological

•           Cap. Ampicillin 500 mg every 6 hours.

•           Tab. Metronidazole 400 mg every 8 hours.

•           Bulk laxative to relieve and avoid constipation.

C.  Definitive treatment

Fistulotomy (laying open of the fistula tract), fistulectomy (excision of the fistula tract) and use of Seton. Secondary fistula needs treatment of primary disease. High level fistula may need proximal colostomy for treatment.

D.  Patient education

•           Do not take treatment for anal disorders like abscess and fistula from unqualified persons.

•           Avoid constipation and take bulk laxatives. Maintain local hygiene.