WHAT IS A PERIANAL FISTULA?

A fistula is a tunnel (channel or path) connecting two separate parts or spaces that are not supposed to communicate. When one opening of this tunnel is inside the intestine and its other end opens to the skin around the anus, we call it a perianal fistula. It is a common disease of the anorectal region. Particularly complicated fistulas are not favorites of surgeons. Perianal fistulas are seen in every 8-10 individuals per 100,000 people in the population. They are 2-7 times more common in males.

WHY DO PERIANAL FISTULAS DEVELOP?

Current information is that they develop due to clogging of the anal glands (anal crypts) that lubricate the anal canal. Consequently, infections may develop and open to the surface. Of all perianal fistulas, 50-70% develop following a previously developed abscess. While a significant number of abscesses and fistulas develop in this way, fistulas may also develop in patients with inflammatory bowel disease, especially in Crohn’s disease, tuberculosis, and malignant diseases.

Advanced diagnostic methods (endoscopy) should be performed in patients; who fail to recover, suffer from recurrences, and have multiple internal and external openings.

WHAT ARE THE COMPLAINTS?

Patients usually present with a filthy-looking and heavily smelling/odorless discharge coming from the inner and outer openings of the fistula. The person complains that he/she observes contamination and wetness in the underwear all the time.

HOW IS DIAGNOSIS MADE AND TREATMENT CARRIED OUT?

The diagnosis is made by physical examination. It is easy to diagnose, especially in patients with a prominent external opening. It is very important to evaluate the patient thoroughly before the surgery. Therefore, preoperative ERUS (endorectal ultrasonography) or magnetic resonance imaging (MRI) are highly useful radiological examinations that guide surgeons. Whether the patient has undergone surgery previously or has comorbid diseases like Crohn’s disease should be understood. Also, the anal sphincter tone should be evaluated.

Perianal fistulas tend to recur but the treatment outcomes are successful in experienced hands.