Ulcerative Colitis: Pathophysiology, Symptoms, and Complications

Pathophysiology

• Starts in the rectum and progresses proximally through the colon.
• Lesions: Continuous inflammation without skip areas.
• Layers affected:
  • Mucosa and submucosa (well-vascularized).
• Tissue damage:
  • Ulcers develop in the mucosa, coalesce into larger ulcerated regions.
  • Bleeding occurs due to tissue destruction.
• Effects on absorption:
  • Damage interferes with the intestine’s ability to reabsorb water and electrolytes.
  • Results in profuse diarrhea with significant water and electrolyte loss.
• Inflammation:
  • Causes edema and granulation tissue formation.
  • The inflamed tissue is fragile and prone to bleeding.

Serious Complications

• Toxic megacolon: Severe dilation of the colon.
• Bacterial leakage:
  • Due to ulceration, bacteria can infiltrate the bloodstream causing septic shock.
• Obstructions:
  • Edema and scarring impair peristalsis and cause bowel obstruction.

Signs and Symptoms

• Severe diarrhea: Up to 12 stools/day.
• Blood in stool:
  • Black tar appearance (melena).
• Cramping and tenesmus: Urgency to defecate.
• Painful: Significant abdominal discomfort.
• Fever: Due to inflammation.
• Weight loss: From malabsorption and reduced intake.
• Emotional impact:
  • House-bound feeling, urgent bathroom needs, and embarrassment.

Treatment Strategies

• Anti-inflammatory drugs:
  • Glucocorticoids.
  • Immunosuppressants.
• Anti-motility agents: To reduce diarrhea.
• Nutritional support:
  • Low-residue diet (limited fiber to reduce bowel activity).
  • Supplements as needed.
• Antimicrobials: For infections or bacterial peritonitis.
• Surgical resection:
  • Remove severely damaged colon sections.

• Psychological support: Coping with chronic illness.

Risks & Long-term Management

• Cancer risk:
  • Increased risk of colorectal cancer.
• Monitoring: Regular screening for dysplasia or malignancy.

Comparison: Crohn’s Disease vs. Ulcerative Colitis Table – add here