Diverticulosis: Causes and Epidemiology

Diverticulosis

• Diverticulosis occurs when small, bulging pouches (diverticula) develop in the digestive tract.

Epidemiology

• Overall prevalence: 12% to 49%
• Increases with age:
  • < 10% in those younger than 40 years
  • > 50% to 66% of patients 80 years
• As common in men and women
• Men: higher incidence of diverticular bleeding
• Women: more episodes of obstruction or stricture
• Disease of Western civilization, extraordinarily rare in rural Africa and Asia
• Highest prevalence rates: United States, Europe, and Australia
• Increases with urbanization

Risk Factors

• Increasing age
• Dietary meat intake
• Living in Western countries (e.g., United States, Western Europe, Australia)
• Connective tissue diseases
• Decreased risk:
  • High dietary fiber intake
  • Living in predominantly rural Asian or African countries (e.g., Kenya, Jordan, Thailand)

Factors That Influence the Risk for Diverticulosis

• Location:
  • In Western countries: left colon (90% sigmoid, 15% right-sided)
  • In Asian countries: right-sided

Spectrum of Diverticulosis

• Uncomplicated diverticulosis:
  • Asymptomatic diverticulosis
  • Symptomatic uncomplicated diverticular disease (SUDD)
• Complicated diverticulosis:
  • Diverticulitis:
    • Uncomplicated diverticulitis: localized phlegmon
    • Complicated diverticulitis: abscess, free perforation with peritonitis, fistula, or obstruction
  • Bleeding

Diagnosis

• Plain films: abnormal in 30% to 50%
• Contrast enema examinations: only water-soluble contrast enemas (e.g., Gastrografin) should be used
• Computed tomography (CT):
  • Diagnostic procedure of choice for acute diverticulitis
  • CT criteria for diverticulitis:
    • Presence of diverticula
    • Pericolic infiltration of fatty tissue (fat stranding)
    • Thickening of the colon wall
    • Formation of abscesses
• Endoscopy:
  • Avoided in suspected acute diverticulitis due to risk of perforation
  • Electively performed 1-3 months after acute phase to exclude competing diagnoses, particularly neoplasia

Management

• Outpatient management:
  • Mild symptoms
  • No peritoneal signs
  • Ability to take oral fluids
  • Supportive home network
  • Treatment with clear liquid diet and antibiotics
• Hospitalization:
  • Elderly
  • Immunosuppressed
  • Severe comorbidities
  • High fever / significant leukocytosis
  • Bowel rest / intravenous fluid
  • Broad-spectrum intravenous antibiotics
• Complicated diverticulitis:
  • Abscess:
    • Small pericolic abscesses: noninterventional management with broad-spectrum antibiotics and bowel rest
    • Percutaneous catheter drainage: CT-guided percutaneous drainage of abdominal abscesses