What is an anal fistula?

An anal fistula is a small tunnel that goes from the glands just inside your anus through to the skin near your anus. This painful condition often results from an infection near your anus or rectum. The infection might not have healed properly. Instead, it created a small cavity filled with pus. Fifty percent of people who develop these cavities, known as abscesses, develop fistulas.

Causes of an anal fistula

The glands around your anus produce fluid. These glands can get blocked. This can cause a bacterial infection. When that happens, a swollen cavity fills with infected pus. This infection can grow as your body tries to fight it. The infection can eventually puncture a hole in your skin. This creates an anal fistula. It's your body's attempt to drain the pus.

Risks of an anal fistula

If you have an anal abscess, you have a high risk for getting an anal fistula. Other risk factors are rarer. They include illnesses that can affect your bowels. Other factors that contribute to getting an anal fistula include:

  • Crohn's disease
  • Sexually transmitted diseases
  • Other conditions such as tuberculosis, cancer or diverticulitis

Symptoms of an anal fistula

Anal fistulas are painful. They cause swelling around your anus. You may experience pain with the pressure of bowel movements. You might bleed in between and during bowel movements. Other symptoms include:

  • Bloody, foul-smelling pus that comes from an opening in your skin near your anus
  • Irritation around your anal skin
  • More than one anal abscess
  • Feelings of fatigue
  • Fever

Diagnosis of an anal fistula

Sometimes the fistula is very easy to spot. Sometimes it isn't. If you're experiencing any of the symptoms, your doctor does a physical exam. This includes looking at your rectal area. You may need to see a specialist for further exams. The specialist may want to do tests like X-rays to take pictures of the inside of your body.

The doctor may need to use tools to examine your anus. This helps them find a fistula that hasn't broken the skin. This process can be painful. You may need to take medications that make you sleep through the exam. After a diagnosis, your doctor might want to do other tests. This helps them make sure you don't have a more serious health condition.

Treatments for anal fistula

You may experience less pain when the fistula drains its pus. But, the infection can continue to affect you until the fistula heals inside your body. You may need to have surgery. If the fistula is very deep, the surgery may be a two-part process. This allows the fistula to drain for at least six weeks before the final surgery takes place. Other treatments can include the following:

  • Warm baths can reduce the pain and discomfort from surgery.
  • Your doctor may prescribe pain pills to help ease any suffering while your body heals.
  • Laxatives or stool softeners can make it easier and less painful to move your bowels after surgery.

Many patients have such good success with surgery for anal fistulas. It's possible that you might be able to have the procedure in your doctor's office or clinic instead of a hospital.

Recovery from an anal fistula

As your body heals, you will likely experience discomfort and may also have a hard time controlling your bowels. Be sure to eat a high-fiber diet and relax as you recover. It's possible that another abscess will form, even after surgery. Discuss this possibility with your specialist to manage your condition.

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