As of Friday, March 22, 2013
DEAR DOCTOR K: My daughter has just been diagnosed with Crohn’s disease. What is it, and what is the treatment?
DEAR READER: Crohn’s disease is an inflammatory bowel disease that causes abdominal pain, diarrhea, loss of appetite, joint pains, weight loss, weakness and fatigue. It’s caused by inflammation of the small (and sometimes the large) intestine.
No one knows for sure what triggers Crohn’s disease. An infection with bacteria that live in the intestines may start the process by activating the immune system. The immune system stays active and creates inflammation.
Usually, Crohn’s disease symptoms come and go. They may go away completely, and then return. For many of my patients with this disease, this on-again, off-again course of the disease is the most difficult thing to deal with. After a few relapses, people live every day wondering if the disease is going to return again.
The inflammation of Crohn’s disease involves the inside lining and deeper layers of the intestine wall. The inside lining can thicken or wear away in spots. This creates ulcers, cracks and fissures — little tunnels that burrow through the wall of the intestine and sometimes spill infected material into the inside of the abdomen. Ulcers and inflammation can occur in all areas of the digestive tract, from the mouth to the rectum. (There’s an illustration on my website, AskDoctorK.com.) The eyes and joints may also be affected.
There is no cure for Crohn’s disease, but medications can effectively improve symptoms. Most of the drugs work by preventing inflammation in the intestines.
A group of drugs called aminosalicylates is usually the first treatment choice. These drugs suppress inflammation in the intestine and joints. They can be taken by mouth as pills, or by rectum as an enema.
Certain antibiotics kill bacteria in irritated areas of the bowel and may decrease inflammation. In people who have diarrhea from the disease, antidiarrheal medications such as loperamide (Imodium) may be helpful.
Other, more powerful anti-inflammatory drugs may be helpful. But they can suppress your immune system, increasing your risk of infections. They are not often used on a long-term basis.
The newest drugs approved for Crohn’s disease are called tumor necrosis factor (TNF) blockers. TNF is a substance made by immune system cells that causes inflammation. TNF blockers have very serious side effects. They are generally prescribed for moderate to severe Crohn’s disease that hasn’t responded to other therapies. Infliximab (Remicade) and adalimumab (Humira) are TNF inhibitors.
Surgery to remove a section of the bowel is another possible treatment. It is usually reserved for severe cases.
When I was in medical school, Crohn’s disease — and another inflammatory bowel disease called ulcerative colitis — were thought to be caused by psychological problems. Why was this? In my opinion, it’s because doctors were unable to figure out what caused it, so they assumed it must be psychological. Today, we know that certain genes are linked to the disease, and that the gut’s immune system is overactive. Crohn’s disease is not in a patient’s head; it’s in her digestive tract.
Dr. Komaroff is a physician and professor at Harvard Medical School. To send questions, go to AskDoctorK.com, or write: Ask Doctor K, 10 Shattuck St., Second Floor, Boston, MA 02115.