Gastrointestinal System Disorders Q 39

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Which of the following factors is believed to be linked to Crohn’s disease?

  

    A. Constipation

    B. Diet

    C. Hereditary

    D. Lack of exercise

    

    

Correct Answer: C. Hereditary

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Although the definite cause of Crohn’s disease is unknown, it’s thought to be associated with infectious, immune, or psychological factors. Because it has a higher incidence in siblings, it may have a genetic cause. More than a hundred genes associated with IBD have been identified. In Crohn’s disease particularly, there appears to be a genetic association with phenotypes. Specifically, NOD2/CARD15 mutations were found to be associated with a phenotype of Crohn’s disease which was associated in those diagnosed at a younger age

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Option A: Constipation does not cause Crohn’s disease. Although the exact etiology of inflammatory bowel disease (IBD) is not known, there is substantial evidence to suggest that the disease is resulting from an inappropriate immune response in the bowel to situations from environmental factors such as drugs, toxins, infections or intestinal microbes in a genetically susceptible host.

Option B: Diet is not a cause of Crohn’s disease. In the future, genotyping could potentially provide prognostic information on the severity of the disease. Furthermore, it could predict which patients should be considered for surgical management vs. medical management based on a more detailed understanding of genetic analysis.

Option D: Lack of exercise does not cause Crohn’s disease. This condition results from a combination of genetic, environmental, and lifestyle factors, many of which are unknown. Many of the major genes related to Crohn’s disease, including NOD2, ATG16L1, IL23R, and IRGM, are involved in immune system function.

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