Inflammatory Bowel Disease

Definition

  • Ulcerative colitis (UC): inflammation of the colonic mucosa; contiguous, starting at rectum
  • Crohn’s disease (CD): transmural inflammation anywhere along GI tract, skip lesions

Epidem & pathophys (Lancet 2016;387:156 & 2017;390:2769)

  • Prevalence ~1-3:1000 in N Am; ↑ incidence in Caucasians, Jews, newly industrialized
  • Age of onset 15–30 y; ? bimodal w/ 2nd peak at 50–70 y; 1:1 M:F in N America
  • Smokers at ↑ risk for CD, whereas nonsmokers & former smokers at ↑ risk for UC
  • Genetic predisposition + environmental risk factors → T cell dysregulation → inflammation