Crohn’s disease is an autoimmune disease that can cause inflammation in any part of your digestive or gastrointestinal tract. One of the complications that can occur with Crohn’s is the development of sores or ulcers that tunnel through the intestine and into the surrounding tissue. These tunnels are called fistulas and often appear around the anus and rectum. Approximately half of all adults with Crohn’s disease will develop a fistula during their lifetime with many of these appearing in the anal area.
How anal fistulas begin
Anal fistulas usually begin in the anal glands, which drain into the anal canal. The anal canal is located at the end of the large intestine between the rectum and anus. If drainage from the anal canal becomes blocked an infection can occur between the inside of the anus and the skin surrounding the anus. This area of skin is sometimes referred to as the perineum. As pus collects (called an abscess) the abscess increases in size and tends to work its way to the surface. The tunnel or track that develops from this process is called a fistula. This tunnel can pass pus, bacteria and fluids to surrounding organs, such as the bladder, vagina or skin.
Initial treatment of anal fistula usually involves draining the blocked glands. Some patients may need repeated draining procedures to keep the infection under control. This may involve the placement of small plastic drains in the fistula, called a “seton". Setons can be helpful toward maintaining an infection-free fistula, and can help with definitive repair. Because it is an infection, antibiotics may also be used but often prove to be inadequate. Biologic mediations, such as Remicade and Humira, have shown to be very helpful in gaining control of the infection and healing the fistulae, if treated in the early stages. If symptoms do not respond to medication, surgery may be needed to prevent spread of the infection to the rest of the body.
Surgery for anal fistulas
Surgery for anal fistulas is not a cure but an intervention to control infection. The most common surgical procedure is called a fistulotomy, which opens the fistula tract. The goal is to repair the anal fistula while avoiding damage to the nearby sphincter muscles, which are necessary for control of the bowel. Damage to the sphincter muscles can result in fecal incontinence.
Specific treatment of anal fistula depends on the location and the complexity of the fistula. In a typical fistulotomy, the surgeon cuts the fistula tract, and scrapes out the infected tissue. If the fistula is more complex there is a higher risk of damage to the sphincter muscles. Advanced approaches of fistula repair, such as flaps may be required to cover the fistula opening with healthy tissue. The post-surgical recurrence rate for anal fistulas in Crohn’s disease is high and attempts at definitive surgery may cause problems with incontinence. Any approach at definitive repair requires a careful discussion with your surgeon and your gastroenterologist.
Considerations before surgery
Because every patient’s disease pattern is unique, you must form a plan that is designed to meet your individual needs. Before making a final decision, it’s helpful to understand why you may need surgery, to educate yourself about the different surgical options, and to ask questions of your doctor and surgeon. You also may want to speak with patients who have undergone the procedure you are considering.
Surgery for Crohn’s disease is never a decision that is taken lightly. All surgery carries some risks. Some risks are common to all surgeries and some are specific to the individual procedures. Ask your surgeon to explain all of the relevant risks associated with the procedure as they pertain to you and your individual condition.
Outside of emergency procedures, a decision to perform surgery should be made in collaboration with your doctor and surgeon. It’s important to seek out a surgeon who has significant experience working with Crohn’s disease. And don’t forget to think of yourself as part of your healthcare team. In fact, you are the most important member of your healthcare team and your voice counts as much as anyone’s.