Fistula

A fistula is an abnormal tunnel or connection that forms between two organs or vessels that do not usually connect, or between an organ and the outside of the body. These tunnels can develop in many different parts of the body, such as the digestive tract, urinary tract, or around the anus. They often result from infection, inflammation, or injury, leading to symptoms like pain, discharge, and discomfort.

What is Fistula?

A fistula is an unusual, tunnel-like connection that develops between two body parts that are not normally joined, or between an internal organ and the skin's surface. Think of it like an unwanted shortcut inside your body. These abnormal passages can occur anywhere, but they are commonly found in the digestive system, urinary system, and around the anus, often causing various uncomfortable symptoms.

Fistulas are essentially tubes or channels that bypass normal anatomy. For example, a fistula might connect two loops of the intestine, or it might connect the intestine to the skin. They can also form between the rectum and the skin near the anus (anorectal fistula), or between the vagina and the bladder (vesicovaginal fistula). These abnormal connections can allow fluids, such as stool, urine, or pus, to leak from one area to another, or out of the body. This leakage can lead to ongoing irritation, infection, and other complications. The specific location of a fistula determines its name and the particular symptoms it causes.

Symptoms

Symptoms of a fistula vary greatly depending on its location, but common signs often include pain, swelling, and a persistent discharge of pus, blood, or other fluids. You might also notice skin irritation around the opening of the fistula, fever, or a general feeling of being unwell. These symptoms can range from mild discomfort to severe pain and can significantly impact daily life.

For a fistula around the anus (anorectal fistula), symptoms often include pain and swelling around the anus, a throbbing pain that worsens when sitting, moving, or having a bowel movement, and bloody or foul-smelling discharge from an opening near the anus. You might also experience fever and chills if an infection is present. Fistulas in other areas, such as between the intestine and the skin (enterocutaneous fistula), can cause abdominal pain, fever, and drainage of intestinal contents through an opening on the skin. A fistula between the bladder and the vagina (vesicovaginal fistula) might lead to continuous leakage of urine from the vagina, frequent urinary tract infections, and vaginal irritation. The presence of any unusual discharge or persistent pain should prompt a medical evaluation.

Causes & risk factors

Fistulas often develop as a complication of an infection, inflammation, or injury that creates an abnormal pathway. Common causes include inflammatory bowel diseases like Crohn's disease, diverticulitis, and complications from surgery or radiation therapy. Certain infections, such as tuberculosis, can also lead to fistula formation. Anyone can develop a fistula, but some conditions increase the risk.

One of the most common causes of anorectal fistulas is an infection in an anal gland that leads to an abscess (a pocket of pus). If this abscess doesn't heal properly or drains incompletely, it can form a tunnel to the skin. Inflammatory bowel diseases, particularly Crohn's disease, are a significant risk factor for various types of fistulas, including those affecting the intestines, anus, and other organs. About 1 in 4 people (25%) with Crohn's disease will develop a fistula. Other potential causes and risk factors include complications from abdominal surgery, especially if there's an infection or poor healing. Radiation therapy for cancer in the pelvic area can also damage tissues and increase the risk of fistula formation. Diverticulitis, a condition where small pouches in the colon become inflamed or infected, can sometimes lead to fistulas. Trauma, such as childbirth injuries, can also cause fistulas, particularly those involving the vagina and bladder or rectum.

How it's diagnosed

Diagnosing a fistula typically involves a physical examination, where a doctor may be able to see or feel the opening of the fistula. Imaging tests are often necessary to map the full extent of the tunnel and identify its internal connections. These tests help doctors understand the fistula's path and plan the most effective treatment, ensuring an accurate diagnosis is made.

During a physical exam, especially for an anorectal fistula, a doctor might look for an opening near the anus and gently feel the area. They may also perform a digital rectal exam. For other types of fistulas, the physical exam will focus on the affected area, looking for signs of discharge or inflammation. To visualize the fistula's internal structure, several imaging tests may be used. These can include a fistulogram, where a dye is injected into the external opening of the fistula before an X-ray is taken. Magnetic resonance imaging (MRI) or computed tomography (CT) scans can provide detailed images of the soft tissues and help identify the fistula's path and any associated abscesses. Endoscopic procedures, such as a colonoscopy or sigmoidoscopy, might be used to examine the inside of the digestive tract and locate internal openings of fistulas, especially in cases related to inflammatory bowel disease.

Treatment options

Treatment for a fistula usually involves surgery to close the abnormal connection, though the specific procedure depends on the fistula's location, size, and complexity. The primary goals are to eliminate the fistula, drain any infection, and prevent recurrence. Non-surgical options, such as antibiotics or special glues, may be considered for certain types of fistulas or to manage symptoms before surgery.

Many fistulas, especially anorectal fistulas, require surgical intervention. The type of surgery depends on how much muscle is involved and the fistula's path. Common surgical procedures include a fistulotomy, where the fistula is cut open, scraped clean, and allowed to heal flat. For more complex fistulas, a seton (a surgical thread) might be placed to help drain the fistula over time, or a flap procedure might be used to cover the internal opening. Other surgical techniques include LIFT (ligation of the intersphincteric fistula tract) procedure, or using a fistula plug made from biological material. For fistulas related to Crohn's disease, medical management with anti-inflammatory drugs or biologics may be used in conjunction with surgery to help heal the fistula and prevent new ones. Antibiotics are often prescribed to treat any infection associated with the fistula, either before or after surgery. In some cases, especially for very small or simple fistulas, non-surgical approaches like fibrin glue or collagen plugs might be attempted, but these often have lower success rates compared to surgery.

Recovery & outlook

Recovery from fistula treatment, particularly surgery, varies based on the fistula's type and complexity, as well as the specific procedure performed. Most people experience significant relief from symptoms after successful treatment. The outlook is generally good, though some fistulas, especially those linked to chronic conditions like Crohn's disease, may recur or require ongoing management. Following post-treatment care instructions is crucial for healing.

After surgery, you can expect some pain and discomfort, which can be managed with medication. Wound care is essential and may involve regular cleaning and dressing changes to promote healing and prevent infection. Depending on the type of fistula and surgery, recovery time can range from a few weeks to several months. It's important to follow your doctor's instructions regarding activity levels, diet, and medication. For anorectal fistulas, successful surgery often leads to complete healing. However, there is a risk of recurrence, especially if the underlying cause, such as Crohn's disease, is not managed. For people with Crohn's disease, fistulas can be a chronic issue, and treatment often involves a combination of medication and surgery to control inflammation and manage the fistula. Regular follow-up appointments with your doctor are important to monitor healing and address any new symptoms or complications. While treatment can be challenging, most people achieve a good quality of life after successful fistula management.

When to see a doctor

You should see a doctor if you experience any persistent symptoms that suggest a fistula, such as ongoing pain, swelling, or unusual discharge from any part of your body. Seek immediate medical attention if you develop a high fever, severe pain, or signs of a widespread infection, as these could indicate a serious complication like sepsis, which requires urgent care.

It is important to consult a healthcare provider if you notice any of the following: persistent drainage of pus, blood, or other fluids from an opening on your skin or from a body orifice (like the anus or vagina); unexplained pain or swelling in any area; or recurrent infections. These symptoms could indicate the presence of a fistula that requires diagnosis and treatment. Seek emergency medical care if you experience signs of a severe infection or complications. These include a sudden high fever (over 100.4°F or 38°C), chills, severe and worsening pain, significant redness or swelling around a suspected fistula, or a general feeling of being very unwell. These could be signs of a spreading infection (cellulitis) or a more serious condition like sepsis, which is a life-threatening response to infection and needs immediate medical attention.

Frequently asked questions

Can a fistula heal on its own without treatment?

Most fistulas do not heal on their own and typically require medical intervention, often surgery, to close the abnormal connection. While some very small or simple fistulas might occasionally close, it is rare. Without proper treatment, fistulas can lead to ongoing pain, infection, and other complications, making it important to seek a doctor's evaluation.

Are all fistulas painful?

Not all fistulas cause severe pain, but many do, especially if there is an active infection or inflammation. The level of pain can vary greatly depending on the fistula's location, size, and whether it's draining properly. Some fistulas might cause only mild discomfort or irritation, while others can lead to intense, throbbing pain.

What is the difference between an abscess and a fistula?

An abscess is a localized collection of pus, usually caused by a bacterial infection. A fistula, on the other hand, is an abnormal tunnel that often forms as a complication of an abscess that has not healed completely or has drained. The fistula creates a pathway for pus or other fluids to escape from the original infection site.

Can diet affect a fistula?

While diet doesn't directly cause or cure a fistula, it can play a role in managing symptoms, especially for fistulas related to inflammatory bowel diseases like Crohn's. Eating a balanced diet and avoiding foods that trigger digestive upset can help reduce inflammation and discomfort. Your doctor or a dietitian can provide specific dietary recommendations tailored to your condition.

How long does recovery take after fistula surgery?

Recovery time after fistula surgery varies widely depending on the type of fistula, the complexity of the surgery, and individual healing factors. It can range from a few weeks for simpler procedures to several months for more complex cases. Your doctor will provide specific post-operative care instructions and a timeline for your recovery.

Can fistulas recur after treatment?

Yes, fistulas can recur even after successful treatment. The risk of recurrence depends on several factors, including the type and complexity of the fistula, the underlying cause (such as Crohn's disease), and how well the initial treatment addressed all aspects of the condition. Regular follow-up with your doctor is important to monitor for any signs of recurrence.

Sources

• MedlinePlus — Fistula
• Mayo Clinic — Fistula
• Cochrane Library — Fistula