Perianal fistula crohn’s disease

Evaluation of Perianal Fistulas in Patients With Crohn’s Disease


Crohn’s disease is a chronic inflammatory disorder that can affect any part of the gastrointestinal tract from the mouth to the anus. The disease is characterized by transmural inflammation that can be complicated by the development of fibrotic strictures, perforation, abscess formation, and fistulization. Perianal fistulas may arise from inflamed or infected anal glands (fistula-in-ano) and/or penetration of fissures or ulcers of the rectum or anal canal. Classification of fistulas in Crohn’s disease is based on the origin and terminus of the fistulous tract. Fistulas may develop between 2 segments of bowel (enteroenteric fistula), a segment of bowel and an adjacent organ (eg, enterovesicular), or between a segment of bowel and the skin (enterocutaneous). Fistulas that communicate with the skin are known as external fistulas; those that communicate with adjacent structures within the abdomen and pelvis are known as internal fistulas. Population-based estimates of the lifetime risk of fistula development in Crohn’s disease range from 14% to 38%. The development of fistulas may precede or coincide with the diagnosis of Crohn’s disease. One cohort study estimated the rate of fistula formation preceding the diagnosis of Crohn’s disease to be 45%. Rates of spontaneous fistula closure are low, with estimates ranging from as low as 6% to 13% in placebo-treated patients in randomized controlled trials of 6-mercaptopurine (6-MP) and infliximab. Spontaneous remission rates of simple fistulas-in-ano have been reported to be as high as 50%.

Fistulas: What You Need to Know About a Common Side Effect of Crohn’s

  • Blood tests to detect infection
  • Special imaging tests, such as computerized tomography (CT) scans or magnetic resonance imaging (MRI) scans to view the fistula

The surgeon may also want to perform an anoscopy, says Dr. Ashburn. For this exam, the doctor inserts a small tubular instrument called an anoscope into the anus to view problems in the anal canal.

The first line of treatment used to be antibiotics for small, simple fistulas. But newer data supports the use of biologic drugs that block tumor necrosis factor alpha (TNF-alpha), a protein that can contribute to inflammation, says Adam Ehrlich, MD, MPH, an assistant professor of medicine at the Lewis Katz School of Medicine at Temple University in Philadelphia.

If Surgery Is Needed

Surgeons may decide to drain abscesses that they find during an exam while you’re under anesthesia. They may also place a seton, which is a heavy suture or latex loop, to prevent new abscesses from forming, says Shannon Chang, MD, gastroenterologist and assistant professor of medicine at NYU Langone Medical Center in New York City.. The seton typically stays in place for “months to years,” she says.

In severe cases, patients may benefit from having an ostomy to allow the anal area to rest and heal, says Ashburn. This procedure involves diverting the intestine to an opening on the abdomen called a stoma, where waste can drain into a bag. This surgery requires a short hospital stay and can be reversed after the anus heals. Or, “if the patient is happy with the ostomy, it can be kept for as long as he or she likes,” she says.

In Omprakash’s case, she needed seven surgeries almost back to back over a one-year period and a prescription for biologics, so recovery was complicated and slow, taking well over a year. She was taking the new drug for about eight months before the fistulas finally closed up.

“The J-pouch was causing the fistula because all these ulcers were coming into the vaginal wall. So they removed the pouch, but I had to have several surgeries to correct the excision, and they pulled out several pieces of J-pouch that had been left inside,” she said. “I also had a massive pelvic abscess with a fistula emerging from it they had to remove. The fistula was heading for my tailbone and could have paralyzed me, so they removed it.”

Along with these corrective surgeries, Omprakash has finally found a drug that works for her to prevent a recurrence of fistulas.

New Frontiers in Treatment for Fistulas

Ligation of the intersphincteric fistula tract (LIFT) is one of the latest advances in surgical techniques used for fistula treatment. LIFT is a two-stage treatment process that enables access to the fistula between the sphincter muscles so surgeons can avoid cutting them. First, a seton band is placed into the fistula tract, forcing it to widen over time. After several weeks, the infected tissue is removed and the internal opening is closed.

“It has a 50 percent success rate,” says Phillip Fleshner, M.D, director of colorectal surgery at Cedars-Sinai Medical Center in Los Angeles.. “You make a little incision on the outside, and you don’t injure the muscle, two very important things in Crohn’s, because that could lead to wounds that don’t heal and interfere with control of stool.”

There are several other novel therapies currently under development to treat fistulas. Researchers at the Odense University Hospital and Aarhus University Hospital in Denmark are conducting a clinical trial on stem cell therapy. Stem cells are cells that can transform into almost any type of tissue in the body, and they could be one treatment option for fistulas.

In this study, which was published in February 2019 in the journal Gastroenterology, researchers took stem cells from the fat tissue in patients to create a tissue plug that surgeons placed in the fistula, enabling it to heal. The Mayo Clinic conducted a phase 1 clinical trial on a similar stem cell therapy that shows promising preliminary results. The results of that research were published in July 2017 in the journal Gastroenterology.

Alofisel (darvadstrocel) is one stem cell therapy that has been approved in Europe for the treatment of complex perianal fistulas in adults, and it’s awaiting approval in the United States. It targets the proliferation of activated lymphocytes (white blood cells that form a main part of the body’s immune cells) and reduces inflammatory cytokines (small proteins).

More Awareness Equals Better Management

Omprakash has been fistula-free for nearly three years. Today she is a patient advocate, with her own blog through which she aims to reduce the stigma surrounding Crohn’s and fistulas. She also runs two support groups for Crohn’s, one for women and one for teens, in New York City, to help people deal with the emotional impact of living with Crohn’s and its side effects.

“Having a fistula was one of the worst experiences. No one knows you have it, but it consumes you,” she says. “As a woman, it really tears apart your womanhood. It hits such a private area and feels very violating.”

She says the best way to manage the disease is to have a strong connection to your doctor, and be sure he or she is really listening to you, and not dismissive of your symptoms. Second opinions do help, and if you’re not making progress with a line of treatment after a few months, it may be time to switch doctors or treatments.

Treatments have come a long way since Omprakash was diagnosed; she says there is a lot more hope for patients with fistulas today and many more pathways they can pursue.

“At the end of the day, it’s about how you approach it,” she says. “I’ve accepted that I have multiple conditions, and it’s about survival, maintaining a good quality of life, and being as ‘normal’ as I can. At least half the battle is accepting the condition.”

Anal Fistula

  • Fistula probe. A long, thin probe is guided through the outer opening of the fistula. A special dye may be injected to find out where the fistula opens up on the inside.

  • Anoscope. This is a special scope used to look inside your anal canal.

  • Imaging studies. These may include an ultrasound, which creates an image of the anal area using sound waves. Or they may include an MRI, which makes images of the area by using special magnets and a computer.


Once you have an anal fistula, antibiotics alone will not cure it. You will need to have surgery to cure the fistula. Surgical treatment options include:

  • Fistulotomy. This procedure opens up the fistula in a way that allows it to heal from the inside out. It is usually an outpatient procedure. This means you go home the same day.

  • Filling the fistula with a special glue or plug. This is a newer type of treatment that closes the inner opening of the fistula. The doctor then fills the fistula tunnel with a material that your body will absorb over time.

  • Reconstructive surgery or surgery that is done in stages. This may be an option in some cases.

  • Seton placement. This procedure involves placing a suture or rubber band (seton) in the fistula that is progressively tightened. It lets the fistula heal behind the seton and reduces the risk of incontinence.

Note: Anal fistulas are very common in people with Crohn’s disease. For those with both Crohn’s disease and a fistula, medical therapy is often tried before surgery.


Complications include a fistula that recurs after treatment and an inability to control bowel movements (fecal incontinence). This is most likely if some of the muscle around the anal opening, called the anal sphincter, is removed.

When to call the healthcare provider

Call your healthcare provider if you have symptoms of an anal fistula, especially if you have a history of a previous anal abscess. If you have been treated for an abscess or fistula, let your provider know right away if you have any of the following:

  • Fever

  • Chills

  • Redness

  • Swelling

  • Bleeding

  • Discharge

  • Constipation

  • Trouble controlling your bowel movements

Managing anal fistula

When recovering from anal fistula treatment, make sure to take pain medicine as directed by your surgeon. Finish all of your antibiotics. Don’t take any over-the-counter medicines without first talking to your provider.

Other important instructions may include:

  • Soaking in a warm bath 3 or 4 times a day

  • Wearing a pad over your anal area until healing is complete

  • Resuming normal activities only when you are cleared by your surgeon

  • Eating a diet high in fiber and drinking plenty of fluids

  • Using a stool softener or bulk laxative as needed

Anal fistula – Recovering from surgery

After having surgery to remove an anal fistula, you should be able to move around and eat and drink after the effects of the anaesthetic painkilling medication have worn off.

If the fistula is relatively simple to operate on, you may be able to go home on the same day as the surgery. However, if the fistula is complicated, you may need to stay in hospital for a few days or have further surgery to complete the procedure.

Looking after the wound

After the operation you will need to wear a dressing over the surgical cut until the wound has healed. Your dressings will need to be changed regularly and you will usually be shown how to do this at home.

However, you may need to visit the hospital or GP surgery so they can check how the wound is healing or change the dressing for you. Most wounds take around six weeks to heal.

There may be some bleeding or a discharge from the wound for the first few weeks, particularly the first time you have a bath or go to the toilet.

You may wish to wear a pad, such as a sanitary towel, inside your underwear to avoid staining your clothes. This advice applies to both men and women.

You should see your GP if you have:

  • heavy bleeding
  • increasing pain, redness, swelling or discharge
  • a high temperature of 38ºC (100.4ºF) or over
  • nausea (feeling sick) or vomiting
  • constipation – being unable to empty your bowels for more than three days, despite using a laxative
  • difficulty passing urine


The following tips may help keep the area around the fistula clean and prevent infection or irritation:

  • use warm water and cotton wool to wash the skin, rather than a towel or sponge – pat the skin dry rather than rubbing it, or use a hairdryer on a low setting
  • avoid perfumed products and talcum powder as these can irritate the skin around the fistula
  • you may be prescribed a barrier cream, which can be applied to stop irritants reaching the skin


Painkilling medication

After the anaesthetic has worn off, you may need to take some pain relief medication.

Over-the-counter painkillers such as paracetamol or ibuprofen can normally be used, although you should check with your surgeon before using them. Always read the manufacturer’s instructions.

A 15-minute bath may also help reduce the pain. The bath water should be as warm as you can comfortably sit in.


Laxatives are a type of medicine that can help you empty your bowels. You may be prescribed laxatives to make it easier for you to go to the toilet after your operation.


You may be prescribed antibiotics (medication to treat infections caused by bacteria) to take before and after surgery. These will help reduce the risk of an infection. If you are prescribed antibiotics, make sure you complete the course.


You may need rest for a few days after your operation, but you should avoid sitting still for a long time. Also avoid doing too much walking.

When you are resting, the following tips may help make you more comfortable:

  • wear loose-fitting clothes and underwear
  • lie on your side when on the sofa or in bed
  • pillows or cushions may help make sitting more comfortable – some pharmacies sell cushions designed to relieve pressure when sitting

Returning to normal activities

You can return to work and start to do some gentle exercise when you feel able to.

Ask your surgeon for advice on when you can drive again. This is usually after a minimum of 48 hours.

You should not go swimming until the wound has completely healed.

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