Anal Fistulas Classifications 101

Like anal fissures and hemorrhoids, anal fistulas have varying classifications depending on the severity of the condition. Knowing these classifications is imperative for finding the right anal fistulas treatment and returning to normal. Learn everything you can from here. 

Understanding the Classifications For Anal Fistulas Treatment 

What Are Anal Fistulas?

An anal fistula is a small tunnel that develops between the end of the bowel and the skin surrounding the anus. How does this occur? Typically, it’s a result of an infection in the anal glands. This infection causes pus to build up in the nearby tissue. Once the pus drains away, it can leave behind a small channel.

It naturally causes discomfort and skin irritation with symptoms such as:

  • Skin irritation around the anus
  • A constant, throbbing pain that can worsen when you sit down, move around, pass stool or cough
  • Smelly discharge near your anus
  • Pus or blood after passing a stool
  • Swelling & redness around your anus
  • High temperature (if you also have an abscess)
  • Difficulty controlling bowel movements (depending on the case)

What Causes Anal Fistulas?

As mentioned before, anal fistulas are essentially anal gland infections. Yet, what can cause such an infection? Typically, they can develop after an anal abscess. Or you can get one if the abscess does not heal properly after the pus has drained away. 

However, you can get anal fistulas from other conditions, such as:

Less common causes of anal fistulas include:

  • Crohn’s disease – A long-standing condition involving the digestive system becoming inflamed.
  • Diverticulitis – An infection of the small pouches that can stick out of the side of the large intestine (colon).
  • Hidradenitis Suppurativa – A long-term skin condition that causes abscesses & scarring.
  • Infection with tuberculosis (TB), HIV, herpes, or syphilis.
  • A complication from surgery near the anus.

What Are the Anal Fistulas Classifications?

Every case of anal fistulas is different. Currently, there are four classifications of anal fistulas. Based on the anatomy related specifically to the sphincter complex, these classifications make it easier to help figure out the best form of anal fistulas treatment. 

Here are the four kinds of anal fistulas:

  • Intersphincteric: One of the most common anal fistulas, with about 45% of people getting it, the fistula penetrates through the internal sphincter but spares the external sphincter.
  • Transphincteric: Another rather common case, with around 30% experiencing it, the fistula passes through both the internal & external sphincters.
  • Suprasphincteric: With around 20% of folks with this type, the fistula penetrates through the internal sphincter. It then extends superiorly in the plane between the sphincters to pass above the external sphincter before spreading to the perineum. Typically, this includes horseshoe abscesses.
  • Extrasphincteric: The rarest kind, with only 5% of people developing it, this fistula forms a connection from the rectum to the perineum that extends laterally to the internal & external sphincter. Out of all the classifications, these are the most difficult to treat. The reason being the need to preserve the sphincter complex.

Award-winning, innovative and passionate, N.A. Hemorrhoids Centre is a hemorrhoid clinic in Calgary offering reliable hemorrhoid treatment. As hemorrhoid specialists, we can treat anal fissures, anal fistulas, anal abscesses, anal itching and more. As a naturopathic hemorrhoid clinic with an international reach, our services are the right solution to treat your sensitive and uncomfortable concerns. Contact us today at 403-796-7551 for more information or to book your appointment.