Large Intestine: Diverticulosis

Diverticulosis

Definitions

  • Diverticulosis: Herniated Diverticulum Through the Colonic Wall
  • Diverticular Disease: Clinically Significant or Symptomatic Disease Associated with Diverticulosis
    • Diverticular Bleeding: Bleeding from Diverticulum
    • Diverticulitis: Inflammation of Diverticulum
    • Segmental Colitis Associated with Diverticulosis (SCAD): Segmental Inflammation of the Interdiverticular Colonic Mucosa without Involvement of Diverticular orifices
      • Somewhat Overlaps with Inflammatory Bowel Disease
    • Symptomatic Uncomplicated Diverticular Disease (SUDD): Persistent Abdominal Pain Due to Diverticulum without Evidence of Bleeding or Inflammation
      • Previously Referred to as “Chronic Smoldering Diverticulitis”

Diverticulosis Pathophysiology

  • Herniation of Colonic Mucosa/Submucosa Between the Muscularis Propria
    • “False”/Pulsion Diverticulum
  • Occur at Sites of Vasa Recta Arterial Entrance Through the Muscularis Propria
  • Location: Anywhere Along the Colon
    • Most Common Site:
      • In the West: Sigmoid Colon (95%)
      • In Asia: Right Colon
    • Not in the Rectum – Tenia Splay Out
  • Cause: Increased Intraluminal Pressure & Straining

Risk Factors

  • Western Diet (Low Fiber, High Fat & Red Meat)
  • Obesity
  • Physical Inactivity
  • Tobacco
  • Seeds/Nuts Are NOT Associated with Diverticulosis or Diverticulitis

Prevalence

  • In the West: 5-45%
    • 65% by Age 85
  • In Asia: 13-25%

Treatment

  • Diverticulosis without Diverticular Disease Does Not Need Any Treatment

Diverticulosis 1

Diverticulosis on Colonoscopy 2

Diverticulosis on CT 3

Diverticular Bleeding

Basics

  • The Most Common Cause of GI Bleeding
  • Incidence in Diverticulosis: 5-15%
  • Most Common Source: Right Colon (Often Larger with a Thinner Wall)
  • Cause: Arterial Vasa Recta Disruption
  • 75% Stop Spontaneously
  • 15-25% Lifetime Risk of Rebleeding

GI Bleeding Work-Up

Treatment

  • Primary Tx: Colonoscopy (Clipping, Epinephrine Injection, Cauterization or Band Ligation)
  • If Fails or Unable to Visualize: Angioembolization
  • Surgery:
    • Indications:
      • Continuous Bleeding > 72 Hours
      • Transfusion > 4-6 Unit within 24 Hours
      • Rebleeding on Same Admission
    • Procedure:
      • Bleeding Localized: Segmental Resection/Sigmoidectomy
      • Bleeding Not Localized: Total Abdominal Colectomy

Diverticular Bleeding 4

References

  1. Haggstrom M. Wikimedia Commons. (License: Public Domain)
  2. Niikura R, Nagata N, Akiyama J, Shimbo T, Uemura N. Hypertension and concomitant arteriosclerotic diseases are risk factors for colonic diverticular bleeding: a case-control study. Int J Colorectal Dis. 2012 Sep;27(9):1137-43. (License: CC BY-2.0)
  3. Hellerhoff. Wikimedia Commons. (License: CC BY-SA-3.0)
  4. Kassab I, Dressner R, Gorcey S. Over-the-Scope Clip for Control of a Recurrent Diverticular Bleed. ACG Case Rep J. 2015 Oct 9;3(1):5-6. (License: CC BY-NC-ND-4.0)