Rectal Fistula (pararectal Fistula), Anal Fistula

2024 Author: Josephine Shorter | [email protected]. Last modified: 2023-12-16 21:43

Rectal fistula

A pararectal fistula occurs as a result of metabolic disturbances in the tissue around the rectal ampulla. Most often, this occurs against the background of paraproctitis or proctitis, a symptom of which is an abscess of cellulose.

The main manifestations of an anal fistula are purulent or bloody discharge, pain, itching, irritation of the epidermis of the perianal region.

Regardless of the site of localization, a pararectal fistula is a canal that connects the ampulla of the rectum or the area near the anus with nearby hollow organs.

Causative agents of paraproctitis:

• Colibacillus,
• Staphylococcus aureus,
• Streptococcus,
• Clostridia,
• Tuberculosis.

Rectal fistula is a consequence of acute or chronic proctitis involving the anal crypts (anal sinuses), the space between the sphincters, and the tissue around the rectum. The anal crypt, affected by proctitis, becomes one of the fistula openings located in the thickness of the tissue.

A pararectal fistula is characterized by frequent relapses, it torments the patient, proceeds with severe local symptoms, and significantly worsens overall health. If the disease lasts long enough, the patient's anal sphincter becomes deformed, and the risk of developing cancer of the lower intestine increases.

Content:

• Classification of pararectal fistulas
• Reasons for the appearance of rectal fistula
• Anal fistula symptoms
• Diagnostics
• Rectal fistula treatment
• Forecast and prevention of the appearance of a pararectal fistula

Classification of pararectal fistulas

Depending on the clinical picture, the following forms of pararectal fistula are distinguished:

• An incomplete fistula is a type that does not come to the surface. The canal ends in pararectal tissue, this is an intermediate stage before the formation of a full form. If purulent processes develop, an incomplete fistula finds a way out, transforming into a complete one.
• A complete fistula has one or more inlets that begin on the wall of the rectum and one outlet that ends in the skin near the anus.

Classification by location relative to the sphincter:

• Intrasphincter localization - the fistula has a straight canal, an internal opening in one of the crypts, an external opening near the anus.
• Transsphincter localization - the fistula has branched passages, purulent pockets in the pararectal tissue, scars form in the surrounding tissues. The fistula canal is located under the skin, on the surface or deep in the sphincter.
• Extrasphincteric localization - a fistula arises as a result of acute paraproctitis, has a long twisted course, several exits. The internal opening opens in the area of the anal sinus (crypt).

The degree of complexity of an extrasphincteric fistula:

• The first degree - the fistulous passage is straight and narrow, there are no scars, no infiltration, no abscesses.
• Second degree - the inner opening is surrounded by scar tissue, there are no signs of inflammation.
• Third degree - there is no scar tissue, an inflammatory process develops in the tissue with the formation of pus.
• The fourth degree - the fistula has an enlarged internal opening, infiltrates, scar tissue.

Reasons for the appearance of rectal fistula

The vast majority of cases of pathology is a complication of acute paraproctitis. Due to the penetration of the infection into the pararectal tissue, an abscess forms in the wall of the rectal ampulla. When it is opened, a fistulous tract is formed. Such a complication is diagnosed if the patient does not consult a doctor in a timely manner, or the surgeon limits the radius of surgery.

Diseases or conditions leading to the appearance of a fistula:

• Injury or resection of the rectum;
• Complication of childbirth;
• Breech presentation of the fetus, tears in the birth canal;
• Complication after gynecological operations;
• Crohn's disease;
• Rectal tuberculosis;
• Rectal cancer;
• Rectal diverticulosis;
• AIDS;
• Syphilis;
• Chlamydia.

Anal fistula symptoms

At the onset of the disease, a fistulous opening appears on the skin near the anus. Pus and ichor are released from it, they stain linen, and these traces cannot be overlooked. The patient has to use pads, wash the perianal area, take a sitz bath. These symptoms are joined by itching, maceration of the skin due to constant exposure to secretions, and an unpleasant odor.

With good drainage of the fistula, pain is weak. It increases with chronic inflammation of an incomplete fistula, becomes intense with bowel movements, coughing and long walking.

The periods of exacerbation are followed by periods of remission. Exacerbation occurs if the fistulous passage is clogged with a purulent mass, products of necrosis and granulation. As a result, an abscess is formed, it spontaneously opens, and the separation of pus and ichor is temporarily reduced. Despite this, the external opening of the fistula never heals, after a while the exacerbation is repeated.

During remission, if the patient carefully observes hygiene, he does not feel severe pain or unpleasant symptoms.

However, a long-term illness with frequent exacerbations leaves the following symptoms:

• Insomnia,
• Hyperthermia,
• Weakness,
• Nervousness,
• Headache,
• Asthenization.

Tissue changes arising from the prolonged course of complex forms of the disease:

• Insufficiency of the anal sphincter;
• Deformation of the anal canal;
• Sphincter muscle scars;
• Pectenosis - scarring of the anus canal;
• Anal canal stricture.

Diagnostics

A complete fistula can be diagnosed by visual inspection. There is a fistula opening on the skin near the patient's anus, from which pus and bloody mucus are released. If the fistula has one hole, this is a consequence of acute paraproctitis. Two openings of the fistulous canal to the right and to the left of the anus are symptoms of a horseshoe-shaped pararectal fistula.

Dependence of the nature of the discharge on the shape of the fistula:

• Odorless yellow pus - a condition after paraproctitis;
• Abundant liquid discharge - tuberculous lesion;
• Scanty tiny discharge - fistula after actinomycosis;
• Bloody or bloody discharge are possible consequences of malignancy of the fistulous process.

If the fistula is incomplete, rectal digital examination reveals a single internal opening. Women suffering from this disease must be examined by a gynecologist to exclude a vaginal fistula.

Additional diagnostic methods and their purpose:

• Probing - determination of the direction and branching of the fistula, its localization relative to the sphincter;
• Anoscopy - the study of the shape and length of the fistulous canal;
• Fistulography - X-ray examination with a contrast agent to determine the volume of the fistula;
• Sigmoidoscopy - assessment of the state of the mucous membrane, detection of tumors;
• Irrigoscopy - differentiation from diseases with similar symptoms (cyst of pararectal tissue);
• Sphincterometry - the study of the functionality of the anal sphincter;
• Ultrasonography - comprehensive diagnostics.

Rectal fistula treatment

For a complete cure of a fistula, there is only one radical method - this is surgical intervention. The operation is not performed when the holes are closed during remission, because in this case it is impossible to assess the affected area, healthy tissue can be damaged, or the fistulous passage can not be completely excised.

With an exacerbation of paraproctitis, the surgeon opens the abscess, eliminates the pus, and prescribes treatment with antibacterial agents for the patient. Additionally, physiotherapeutic procedures are used (UFO, electrophoresis). As soon as the inflammatory process subsides, the fistulous canal is excised.

Surgical techniques:

• Dissection of the fistula into the rectal lumen;
• Opening of purulent streaks;
• Drainage of infiltrates;
• Suturing of the sphincter;
• Closing the fistulous opening with a flap of its own muscle and mucous tissue.

The surgeon chooses the technique of the operation depending on the degree of damage and the localization of the fistula relative to the sphincter.

After the operation, complications may occur in the form of insufficiency of the anal sphincter, as well as relapses of the disease. Their likelihood is significantly reduced with timely initiation of treatment and correct operation technique.

Forecast and prevention of the appearance of a pararectal fistula

Intra- and transsphincteric fistulas of low localization respond well to treatment and rarely recur. Deep extra- and transsphincteric fistulas are characterized by a long course of the disease and frequent relapses.

To avoid the appearance of pathology, you need to try to exclude rectal injuries, timely treat paraproctitis.

The author of the article: Volkov Dmitry Sergeevich | c. m. n. surgeon, phlebologist

Education: Moscow State University of Medicine and Dentistry (1996). In 2003 he received a diploma from the Educational and Scientific Medical Center of the Presidential Administration of the Russian Federation.