Understanding Anal Fistula Surgery Complete Guideline 2023

What is an Anal Fistula?

Understanding Anal Fistula Surgery is an abnormal tunnel that forms between the inside of your anus and the skin surrounding it. Typically, it originates from the anal glands located in the upper part of the anus. When these glands become infected, the resulting abscess can create a channel through which infection drains to the skin, leading to the formation of a fistula. This type of infection is known as a perianal abscess. Sometimes, the term “perianal fistula” is used interchangeably with “anal fistula,” referring to its location around the anus.

How Common Are Anal Fistulas?

Anal fistulas are a relatively frequent condition affecting the anorectal region. They are twice as common in men and those assigned male at birth (AMAB). Approximately 50% of individuals who develop an infected anal gland will go on to form a fistula. In fact, an infected gland leading to an abscess is responsible for about 75% of anal fistulas.

Symptoms and Causes

Common Symptoms of Anal Fistulas:

The most common anal fistula symptoms are:

• Anal pain, often intense and throbbing. You may feel it more when you poop, cough or sit. Your butt may be sensitive to touch.
• Swelling and redness (inflammation) inside or around your anus. These are signs of active infection under the skin (cellulitis).
• Fluid drainage from somewhere around your anus. It may include pus, poop or blood (rectal bleeding). It may have a smell.

Less common symptoms include:

• Fever.
• Pain when you pee.
• Difficulty holding your poop in.

You may or may not be able to see the fistula with a mirror.

Less Common Symptoms:

• Fever: Indicative of a more severe infection.
• Painful Urination: Occurs if the infection or inflammation affects nearby structures.
• Difficulty Controlling Bowel Movements: May occur if the fistula disrupts normal muscle function.

Appearance of an Anal Fistula:

An anal fistula typically appears as a small hole near the anus. This hole represents the outer end of the tunnel formed by the fistula. It may discharge pus, blood, or stool, especially when pressure is applied to the surrounding skin. Older fistulas can sometimes close off externally, causing pain and swelling until they reopen for drainage.

Causes of Anal Fistulas

Common Causes:

• Perianal Abscess: The most prevalent cause, usually forming due to an infected anal gland. The abscess creates a drainage channel to the outside as the pus needs to escape, leading to a fistula.

Uncommon Causes:

• Inflammatory Bowel Diseases (IBD): Conditions like Crohn’s disease can lead to fistula formation.
• Anal Sexually Transmitted Infections (STIs): Certain infections can cause fistulas.
• Tuberculosis: Can occasionally affect the anal area and lead to fistula formation.
• Traumatic Injury or Surgery: Previous surgeries or injuries in the anal area can result in fistulas.
• Radiation Therapy: Treatment for pelvic cancers can sometimes lead to fistula formation.
• Actinomycosis: A rare bacterial infection that can cause abscesses in the perianal area.
• Hidradenitis Suppurativa: A chronic skin condition that causes abscesses in sweat glands, sometimes affecting the perianal region.

Risk Factors

You are more likely to develop an anal fistula if you:

• Are male or assigned male at birth.
• Have had a perianal abscess in the past.
• Suffer from inflammatory bowel disease (IBD) such as Crohn’s disease.
• Have undergone surgery or radiation therapy in the perianal area.
• Are immunocompromised or frequently experience infections.
• Have a chronic sexually transmitted infection.

Fistula Pain

Potential Complications

Untreated fistulas rarely heal on their own and can lead to:

• Persistent Infection: Continuous or recurring infections can occur if the fistula is not fully resolved.
• Extension of the Fistula: Chronic fistulas can occasionally branch out, creating more complex pathways that are harder to treat.
• Cancer: Long-standing, untreated fistulas are associated with an increased risk of anal cancer due to chronic inflammation and tissue erosion.

Diagnosis and Tests

Diagnosing an Anal Fistula:

Most anal fistulas can be detected during a physical examination. However, identifying the internal opening within the anus often requires anesthesia. If the examination is too painful, it may need to be conducted under sedation in an operating room.

To pinpoint the internal source of the fistula, your healthcare provider may use tools such as:

• Anoscope or Proctoscope: Lighted scopes that help visualize the anal and rectal areas.
• Hydrogen Peroxide Injection: This can help locate the infection by causing bubbles or foam at the site of the internal opening.

Additional Tests:

• MRI (Magnetic Resonance Imaging): Provides detailed images to map the fistula’s path and its relation to muscles and organs.
• Endoscopic Ultrasound: An internal probe with ultrasound capabilities to visualize the fistula.
• Fistulography: An X-ray taken after injecting dye into the fistula to outline its pathway.

Types of Anal Fistulas

Anal fistulas are classified based on their location relative to the anal sphincter muscles:

• Intersphincteric Fistula: Travels through the internal sphincter and between the internal and external sphincter muscles.
• Transsphincteric Fistula: Passes through both the internal and external sphincter muscles.
• Suprasphincteric Fistula: Starts at the internal sphincter and travels around the external sphincter.
• Extrasphincteric Fistula: Typically originates from the rectum and bypasses both sphincter muscles, not from an anal gland.
• Superficial Fistula: Travels from the lower anal canal to the skin, bypassing the sphincter muscles.

Management and Treatment

Surgical Treatment:

Most anal fistulas require surgery, as they rarely heal spontaneously without recurring infections and abscesses. However, non-infected fistulas caused by inflammatory bowel disease might heal with medical treatment using immunomodulators like infliximab. Fistula surgery is a crucial medical procedure designed to address abnormal connections between two body parts that normally do not connect. These abnormal passages, known as fistulas, can form between various structures such as organs, vessels, or intestines. Fistulas often result from infection, inflammation, injury, or surgery, and their presence can significantly affect a person’s quality of life. This article delves into the intricacies of fistula surgery, covering its types, causes, symptoms, diagnosis, treatment options, and the recovery process.

Simple Fistulas:

For fistulas involving minimal muscle, a fistulotomy is the standard procedure. This involves cutting through the fistula to allow healing from the bottom up, with a high success rate of about 95%.

Complex Fistulas:

Complex fistulas, involving more muscle or multiple branches, may require more intricate procedures:

• Seton Drain: A surgical thread used to keep the fistula open for drainage, which may be left in place indefinitely or followed by additional procedures.
• Endorectal Advancement Flap: Involves covering the internal opening with a flap of healthy rectal tissue to preserve the sphincter muscles. This has a success rate of around 70%.
• LIFT Procedure (Ligation of Intersphincteric Fistula Tract): Closing the part of the fistula between the sphincter muscles with stitches, often following a seton drain. It has a success rate of about 75%.

Risks and Recovery

Risks of Surgery:

• Recurring Infection: If not completely eradicated, infections can persist.
• Recurring Fistula: Fistulas can recur, particularly if caused by chronic conditions or if the initial surgery was complex.
• Fecal Incontinence: Some patients may experience minor incontinence issues post-surgery.

Recovery:

Recovery typically involves:

• Outpatient Surgery: Most patients can go home the same day but may need additional surgeries later.
• Pain Management: Prescription pain medications and measures to prevent constipation, such as fiber supplements and increased water intake.
• Sitz Baths: Regular warm baths to soothe the area and promote healing.
• Wound Care: Keeping the wound clean and changing dressings regularly to manage drainage.

Outlook and Prognosis

Recovery from anal fistula surgery usually takes three to six weeks. The complexity of the fistula determines the recovery process. Some fistulas, especially those caused by chronic conditions like IBD, may recur or require multiple treatments.

When to See a Healthcare Provider

Any significant anal pain warrants a consultation with a healthcare provider. Persistent or severe pain should not be dismissed as hemorrhoids or minor issues. If initial treatments do not alleviate the pain, seeking a specialist such as a gastroenterologist or colorectal surgeon is advisable.

Additional Information

Perianal Vaginal Fistula:

Often referred to as a rectovaginal fistula, this type connects the rectum to the vagina, and it’s usually narrower between these two organs compared to the anus and vagina.

Difference Between Anal Fissure and Anal Fistula:

An anal fissure is a superficial tear in the anal canal lining, causing pain but not creating a tunnel like a fistula. However, an infected fissure can potentially lead to a fistula if it forms an abscess that drains.

Living With

When should I see my healthcare provider about an anal fistula?

Always see a healthcare provider about anal pain. Anorectal conditions that cause significant pain may be serious. Don’t assume it’s something that will go away by itself. Hemorrhoids may be more common and familiar, but they aren’t usually very painful. If a general (primary care) practitioner tells you it’s a hemorrhoid but the pain continues, see a specialist, like a gastroenterologist or colorectal surgeon.

Additional Common Questions

How painful is it after fistula surgery? 

After fistula surgery, pain can be moderate to severe initially. Pain medications are prescribed to manage discomfort. Expect local soreness, tenderness, and swelling. Activities may be restricted to aid healing. Pain typically decreases gradually over days to weeks as healing progresses.

What is a perianal vaginal fistula?

A perianal vaginal fistula is usually called a rectovaginal fistula, because it usually connects from your rectum to your vagina. Your rectum is the part of your large intestine that comes just before your anus. The border between your rectum and vagina is much narrower than between your vagina and anus. A vaginal fistula can develop from any part of your intestines, but it’s usually from your rectum or colon.

What’s the difference between an anal fissure vs anal fistula?

An anal fissure is a split or tear in the lining of your anal canal. It can cause similar symptoms to an anal fistula, but a fissure is a superficial wound. It doesn’t tunnel through your anal wall to your skin the way a fistula does. However, it’s possible that an anal fissure could develop into an anal fistula. If an anal fissure becomes infected, it could form an abscess, which could create an anal fistula when it drains.

Conclusion:

Fistula surgery is a crucial step in managing anal fistulas, designed to alleviate symptoms, prevent complications, and promote healing. While discomfort and pain are expected in the initial post-operative period, they generally subside as healing progresses. Adhering to post-operative care instructions, such as maintaining wound hygiene, taking prescribed medications, and attending follow-up appointments, plays a pivotal role in ensuring successful recovery. Although there are potential risks, including infection or recurrence, these are typically manageable with prompt medical attention. Overall, the goal of fistula surgery is to improve quality of life by resolving symptoms and minimizing the likelihood of future complications.