advertisement

What Causes Crohn's?

Infections

One theory suggests that viruses or bacteria within the intestine may alter properties in the lining and intestinal tract. Over time, these changes may trigger the injurious processes that lead to inflammatory bowel disease.

Measles. Some studies report that children with IBD may have had more and earlier childhood infections. The measles virus has been of particular interest. According to the U.S. Centers for Disease Control, and many studies, the measles virus does not cause Crohn’s or IBD.

Much publicity has centered on whether the vaccine for measles, mumps, and rubella (the MMR vaccine) causes conditions such as autism and Crohn’s disease. This theory has been rigorously reviewed and refuted in many well-conducted studies, including several published in 2006. The evidence clearly indicates that the MMR vaccine does not increase the risk of Crohn’s disease, other inflammatory bowel disease, or autism.

Mycobacteria. A type of bacterium associated with tuberculosis is another possible candidate for an infectious cause of Crohn’s disease.

Escherichia coli. The intestine normally harbors E. coli bacteria. In most cases, the bacteria are harmless and even protective. Some E. coli strains, however, can bind to the intestinal walls and penetrate the lining. These damaging strains may be associated with Crohn’s disease.

Cytomegalovirus. Cytomegalovirus (CMV) is a common virus that is also under suspicion as a contributor to severe cases of IBD.

Dietary Factors

Inflammatory bowel disease is much more prevalent in industrialized nations and in higher-income groups. Experts believe, then, that diet must play some role, although studies have been conflicting over its importance.

---

Review Date: 03/06/2007
Reviewed By: A.D.A.M. Editorial Team: Greg Juhn, M.T.P.W., David R. Eltz, Kelli A. Stacy. Previously approved by Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital (8/21/2006).