Lecture on Inflammatory Bowel Diseases (IBD)

Introduction

• Topic: Inflammatory Bowel Diseases (IBD)
• Main focus on two types: Ulcerative Colitis (UC) and Crohn's Disease (CD)
• Objective: Understand the differences between UC and CD

Inflammatory Bowel Disease (IBD)

• Definition: Disease of the intestine (large or small) characterized by inflammation
• Two main types: Ulcerative Colitis (UC) and Crohn's Disease (CD)

Differences between UC and CD

General Differences

• Crohn's Disease (CD)

  • Affects any part of the gastrointestinal tract, from mouth to anus
  • Often starts at the terminal ileum
  • Features skip lesions (areas of diseased bowel interspersed with normal bowel)
  • Transmural inflammation (affects all layers of the bowel wall)
  • Common complications include fistulas, strictures, and adhesions

• Ulcerative Colitis (UC)

  • Limited to the colon and rectum
  • Begins in the rectum and may extend proximally in a continuous fashion
  • Involves only the mucosa and submucosa layers
  • Continuous colonic involvement (no skip lesions)
  • Can lead to toxic megacolon and increased risk of colorectal cancer

Gross Pathology

• Crohn's Disease

  • Skip lesions present
  • Cobblestone mucosa caused by swollen mucosa between deep ulcers/fissures
  • Thickened intestinal wall leads to a narrowed lumen ("hose pipe" appearance)
  • Deep serpiginous ulcers
  • Granulomas present

• Ulcerative Colitis

  • Continuous involvement starting from the rectum
  • Pseudopolyps (swollen mucosa between superficial ulcers)
  • Thinned intestinal wall with widened lumen ("garden hose" or "pipe stem" appearance)
  • Superficial ulcers

Microscopic Features

• Crohn's Disease

  • Transmural inflammation with lymphocyte infiltration
  • Non-caseating granulomas
  • Deep fissures and fistulas

• Ulcerative Colitis

  • Inflammation confined to mucosa and submucosa
  • Presence of crypt abscesses
  • Neutrophilic infiltration

Serological Findings

• Crohn's Disease

  • Anti-Saccharomyces cerevisiae antibodies (ASCA)

• Ulcerative Colitis

  • p-ANCA (perinuclear anti-neutrophil cytoplasmic antibodies) may be present

Clinical Presentation

• Crohn's Disease

  • Symptoms may include abdominal pain, diarrhea, weight loss, and fatigue
  • Perianal disease common

• Ulcerative Colitis

  • Symptoms include bloody diarrhea, abdominal pain, and urgent bowel movements
  • Associated with periods of remission and exacerbation

Complications

• Crohn's Disease

  • Strictures, fistulas, abscesses, malabsorption

• Ulcerative Colitis

  • Increased risk of colorectal cancer
  • Toxic megacolon

Conclusion

• Both CD and UC are chronic inflammatory conditions of the intestines with distinct differences in pathology and clinical presentation.
• Important to differentiate between the two for appropriate management and treatment.

Additional Notes

• Contact for further study-related questions or assistance in study planning.
• New batch on Community Medicine (PSM) launching soon; students encouraged to participate.

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Study Tip: Focus on understanding the distinct characteristics and complications of both Crohn's Disease and Ulcerative Colitis as they are crucial for diagnosis and treatment in clinical practice.