Inflammatory Bowel Disease (IBD) refers to two conditions: Crohn's disease and ulcerative colitis. Crohn's disease causes chronic inflammation of the gastrointestinal tract that can affect any location from mouth to anus in a discontinuous pattern. Ulcerative colitis causes non-granulomatous inflammation of the colon and rectum in a continuous pattern beginning in the rectum. The causes of IBD are not fully known but involve an immune reaction to environmental triggers in genetically predisposed individuals. Symptoms vary depending on the location and severity of inflammation. Management involves non-pharmacological approaches as well as medications to reduce inflammation like aminosalicates, corticosteroids, immunosuppress
2. INTRODUCTION
• IBD is an idiopathic disease , probably involving an
immune reaction of the body to its own intestinal tract
• Crohn’s disease (CD)
• Ulcerative colitis (UC)
3. INTRODUCTION
• CD is a condition of chronic granulomatous
inflammation potentially involving any location of the
GIT from mouth to anus.
• UC is an non granulomatous inflammatory disorder
that affects the rectum and extends proximally to
affect variable extent of the colon.
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8. EPIDEMIOLOGY
• UC:
15-40 yrs (Young adults)
No variation between between men and women or
between socioeconomic group
High incidence areas: USA and northern-western
Europe
More common in non-smokers
9. EPIDEMIOLOGY
CD
1st
peak 15-30 years of age, 2nd
peak around 60 y
Marginally more common in females
High incidence areas: North America, UK,northern
Europe
More common in smokers
15. Feature UC CD
Location Only colon GIT
Anatomic
distribution
Continuous, begins
distally
Skip lesions
Rectal involvement Involved in >90% Rectal spare
Gross bleeding Universal Only 25%
Peri-anal disease Rare 75%
Fistulization No Yes
Granulomas No 50-75%
DISTINGUISHING CHARACTERISTICS OF CD AND UC
16. Feature CD UC
Transmural inflammation Yes Uncommon
Granulomas 50-75% No
Fissures Common Rare
Fibrosis Common No
Submucosal inflammation Common Uncommon
PATHOLOGIC FEATURES OF CD AND UC
17. UC CD
Collar button ulcers Nodularity
Granularity
RADIOLOGIC FEATURES OF CD AND UC
18. PATHOPHYSIOLOGY
• Bacterial antigens are taken up by specialized M cells, pass
between leaky epithelial cells or enter the lamina propria
through ulcerated mucosa
• After processing they are presented on type 1 T-helper cells by
antigen presenting cells (APC) in the lamina propria.
• T-cell activation and differentiation results in Th1 T cell
mediated cytokine response
• With the secretion of cytokines including gamma interferon
(IFN )ƴ
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21. PATHOPHYSIOLOGY
• Further amplification of T cells perpetuates the inflammatory
process with activation of non immune cells and release of the
important cytokines.
• Eg: IL-12, IL-23, IL-1, IL-6 and tumor necrosis factor (TNF)
• These pathways occur in all normal individual exposed to
inflammatory insults and this is self limiting in healthy subjects
• In genetically predisposed persons, dysregulation of innate
immunity may trigger inflammatory bowel disease.
