An anorectal fistula (Fistula-in Ano)is defined as an abnormal communication between anus and the perianal skin. Fistula is an abnormal passage from one epithelial surface to another surface. This occurs in the form of hollow ways lined with granulation tissue connection of the primary opening inside the anal canal to a secondary opening in the perianal skin. Secondary tracts can be multiple and from the same primary opening.
An anal abscess is the common cause of an fistula in ano. Abscess is a collection of fluid and pus infected and develops into a small gland, just inside the anus and become infected with bacteria. The cause of abscess is unknown, although abscesses are common in people with immune deficiencies like HIV and AIDS.
Other causes of an anal fistula also develop as a result of:
1. A growth of ulcer (painful sore)
2. Complication from anal surgery
3. Congenital abnormality that occurs from birth
4. Irritable bowel syndrome (IBS): a chronic disorders (long term) that affects the digestive system
5. Diverticulitis: the formation of small pouches that will stick to the large intestine (colon) and become infected and inflamed.
6. Ulcerative colitis: this is a chronic condition that causes colon to be inflamed and will cause ulcers to form on lining of the colon.
7. Crohn’s disease: this is a chronic condition that causes inflammation of the lining of the digestive system. Cancer rectum: the rectum is an area at the end of colon where faeces (stools) are stored.
8. Tuberculosis(TB): this is a a bacterial infection that primarily affects the lungs and also spread to many different parts of the body.
9. HIV& AIDS: a virus that attacks body’s immune system (the body’s system of defence against disease and infection).
11. syphilis: a bacterial infection that is passed through sexual contact, injecting drugs or blood transfusions.
Anal fistula causes many different symptoms:
Tools used for diagnosis of fistula in ano include:
Diagnostic tools used for complicated fistulas include:
Flexible sigmoidoscopy can be used to rule out other disorders such as ulcerative colitis or Crohn’s disease.
The surgical procedure and individual treatment plan will depend on the anal fistula’s location and complexity.
1. Fistulotomy:The surgeon finds fistula’s internal opening and cuts the channel (tract) open, scrapes and flushes out and flattens it by stitching its sides to the sides of the incision.
To treat a more complicated fistula the surgeon will lay open only the segment where the channels join and will remove the remaining channels.
The operation is needed to be done in two stages if a significant amount of sphincter muscle must be cut and if the entire channel can’t be found.
2. Advancement rectal flap: Sometimes, to reduce the amount of cutting of the sphincter muscle, the surgeon will be out of the core channel, and cut into rectal wall flap to access and remove the internal fistula opening. The flap is then to be stitched back down.
3. Seton placement: The surgeon will use Seton (a series of silk or rubber band) to either create scar tissue on the part of the sphincter muscle before cutting it with a knife and to allow the seton to cut all the way through the muscle over the course of several weeks. A seton is used to help the fistula to drain.
4. Fibrin glue and collagen plug: In some cases, the surgeon uses fibrin glue, from plasma proteins, to seal and heal a fistula rather than cutting it open. The doctor injects glue through the external opening after clearing the tract and stitching the internal opening and closes external opening. The anal fistula tract is also sealed with a plug of collagen protein and then closed.
5. Ligation intersphincteric fistula tract (LIFT): The first step involves placing a seton into the fistula tract. After several weeks later the tract gets thickened and the surgeon divides fistula tract without dividing the muscle and closes internal fistula opening.
6. Ostomy/stoma:The surgeon will create a temporary opening in the abdomen to divert waste (which is collected in a bag) and allows the anal area to heal.
7. Muscle flap:In complex anal fistulas, the area between the two fistula openings is filled with healthy muscle tissue harvested from the thigh, labia and buttock.
Fissures can be prevented by preventing constipation. To do this, soften stool by gradually adding more fiber to diet, and by drinking 6 to 8 glasses of water daily. Commercially available fiber supplement powders will work well.
It is not always possible to prevent other types of anal disorders but able to decrease risk for these illnesses by:
1. Using gentle techniques to clean anal area
2. Keeping anal area dry by changing underwear frequently and using powder to absorb moisture
3. Always use a condom and practice anal intercourse
4. Never insert any foreign object into rectum.