Crohn's Disease: Drugs Can Reduce the Symptoms

by Food and Drug Administration (FDA)

Thirty-two years ago Ginger Gray walked into her doctor's office complaining of abdominal pain, diarrhea, severe weight loss, and overwhelming joint pain. At 19, she hadn't grown an inch since the sixth grade. But her doctor said there was nothing physically wrong with her, and even suggested she seek psychiatric counseling. Fortunately for Gray, she sought another physician's opinion. Based on tests he conducted, the doctor recommended the 4-foot-11-inch Pennsylvania resident begin full-time treatment for Crohn's disease.

"Crohn's disease robbed me of my stamina," Gray says. "It took two years for me to fully regain my strength and weight so that I could begin working again."

Until now, treatment for Crohn's has relied on surgery and anti-inflammatory and other drugs also used to treat other conditions. In August 1998, the Food and Drug Administration licensed the first treatment specifically for Crohn's disease, an incurable and sometimes debilitating inflammation of the bowel.

Remicade (infliximab) is a genetically engineered antibody that blocks inflammation caused by a protein called tumor necrosis factor. After clinical trials showed benefit from Remicade treatment within a two-to-four week period following a single dose, FDA approved the drug for patients with moderate to severe Crohn's disease who have not found relief with other treatments.

"We recognized that [Remicade] had such a dramatic effect on patients," says Barbara Matthews, M.D., a medical officer in FDA's Center for Biologics Evaluation and Research, "that it was given accelerated approval."

Remicade, which is taken intravenously, can decrease the amount of inflammation along the lining of the intestine. Clinical trials also show that Remicade is effective in closing fistulas (abnormal passages or sores between the bowel and skin). Although not a cure, the drug reduces the symptoms in patients who have not responded well to traditional treatments.

"This is an exciting development for two reasons," says R. Balfour Sartor, M.D., professor of medicine, microbiology and immunology at the University of North Carolina, and chairman of the National Scientific Advisory Committee for the Crohn's & Colitis Foundation of America (CCFA). "It is the first therapy for Crohn's disease derived by molecular techniques, and it has the possibility of improving the quality of life for [Crohn's] patients."

But Sartor also cautions that the long-term toxic effects of Remicade are unknown and that the drug is not needed by every Crohn's disease patient. "Two-thirds of the people will have near immediate results," he says, "but only those patients who do not respond to other therapies" are eligible to take the drug. The next step is to maintain a patient's remission after the drug's initial effect has worn off.

Currently, studies are being done to better define the risks and longer-term benefits of Remicade because drug reactions and potential adverse effects from suppressing tumor necrosis factor require further clarification.

Understanding Crohn's Disease

Crohn's disease is one of two major types of inflammatory bowel diseases (IBD) — the general term for diseases that cause inflammation in the intestines — and has no cure and a high rate of recurrence following treatment. It usually occurs in the lowest portion of the small intestine (ileum), and the large intestine (colon or bowel), but it can occur in other parts of the digestive tract. Crohn's usually involves all layers of the intestinal wall. The disease can be difficult to diagnose because its symptoms, which include chronic diarrhea, crampy abdominal pain, loss of appetite, and weight loss, often mimic those of the other IBD type — ulcerative colitis — which affects only the colon.

"Both illnesses are chronic," says David S. Kaminstein, M.D., former chief of gastroenterology at The Chester County Hospital in West Chester, Pa. "But Crohn's disease often leads to other complications that are less often seen in ulcerative colitis, such as intestinal obstruction."

CCFA estimates that the incidence of Crohn's disease is from 1.2 to 15 cases per 100,000 people in the United States. While it can affect any age group, the onset of the disease most commonly occurs between ages 15 and 30, and between ages 60 and 80.

Kaminstein adds that IBD symptoms are similar to and often mistaken for irritable bowel syndrome. However, in contrast to IBD, the bowel syndrome does not cause inflammation in the intestines.

Researchers believe that Crohn's disease has a genetic basis but does not appear until triggered by an environmental agent such as bacteria or virus. The trigger causes an abnormal activation of the immune system.

According to CCFA, people who have a relative with the disease have at least a 10 times greater risk of developing Crohn's than that of the general population. If the relative is a sibling, the risk is 30 times greater. CCFA says that new technologies are helping researchers close in on the genes that predispose people to IBD.

"There are stories of obstructed bowel and bowel surgery back to my great-great grandfather on my mother's side of the family," Gray recalls, "but they didn't have the sophisticated tools for diagnosing Crohn's back then." Gray's second cousin and a nephew also have the disease.

Diagnosis Tests and Tools

A doctor may suspect Crohn's disease in anyone with recurring, crampy abdominal pain or diarrhea, particularly if the person has weight loss, fever or inflammation in the joints, eyes, and skin. No laboratory test specifically identifies Crohn's disease, but blood tests may show anemia (low red blood cell count), abnormally high numbers of white blood cells, low albumin levels, and other indications of inflammation.

According to Brian E. Harvey, M.D., Ph.D., a medical officer with FDA's Center for Devices and Radiological Health, "Barium enema x-rays have traditionally revealed the characteristic appearance of Crohn's disease in the colon, and barium upper GI with small bowel follow-through for abnormalities in the small intestine." Today, however, a procedure that examines the large intestine with a flexible viewing tube, known as a colonoscopy, along with a biopsy (removal of a tissue specimen for microscopic examination), most commonly confirms the diagnosis.

Another diagnostic tool, computed tomography (CT) or CAT scan, being used more now than previously, shows changes in the wall of the entire intestine and can identify complications such as intestinal obstruction, abscesses, and fistula formation.

About the Author

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