GASTROENTEROLOGY ARTICLE OF THE WEEK
February 18, 2010
Abraham C, Cho JH. Inflammatory Bowel Disease. N Engl J Med 2009;361:2066-78.
1. Observations regarding changes in intestinal microbiome and epithlieum observed in
patients with IBD include:
a. Defective tight junction regulation and increased permeability of the paracellular space
b. An overabundance of Bacteroides species
c. Decreased mucous production leading to defective epithelial repair
d. An inflammatory response that results in increased epithelial injury
2. NOD2 Gene
a. encodes for an intracellular molecule that senses a component found in bacterial walls (peptidoglycan)
b. NOD2 polymorphisms are most often found in African Americans
c. When NOD2 gene polymorphism is present, fibrostenotic disease is more likely
d. People who are homozygotes for NOD polymorphisms will develop Crohn’s disease
3. Which of the following are pro-inflammatory cytokines
a. TGF-β
b. IL-23
c. IL-10
d. TNF-α
True or False
4. The innate arm of the immune system recognizes specific microbial antigens
5. Paneth cells secrete antimicrobial peptides such as α-defensins.
6. The M cells, located over the Peyer’s patches prevent entry of microbes across the epithelium
7. In IBD patients, cells of the innate immune response produce excessive amounts of inflammatory peptides, including TNF-α
8. The adaptive immune response (B & T cells) respond to specific antigens and have immunologic memory
9. After T-cells circulate through mesenteric lymph nodes and Peyer’s patches, some become “gut-tropic” and require adhesion molecules to enter into the intestinal tissue
10. CD4 helper cells do not appear to be involved in the pathogenesis of IBD
12. Ischemia is not considered to be factor in IBD