Diverticulitis

Key Features

Essentials of Diagnosis

• Acute abdominal pain and fever

• Left lower abdominal tenderness and mass

• Leukocytosis

General Considerations

• Defined as macroscopic inflammation of a diverticulum that may reflect a spectrum from inflammation alone, to microperforation with localized paracolic inflammation, to macroperforation with either abscess or generalized peritonitis

• Diverticulosis

  • Present in 25% of adults over age 40

  • Increases with age

  • Most cases are asymptomatic

• Diverticulitis occurs in 10–20% of patients with diverticulosis

Clinical Findings

Symptoms and Signs

• Abdominal pain, mild to moderate, aching, usually in the left lower quadrant

• Constipation or loose stools

• Nausea and vomiting

• Low-grade fever

• Left lower quadrant tenderness

• Palpable left lower quadrant mass

• Generalized abdominal pain and peritoneal signs in patients with free perforation

Differential Diagnosis

• Perforated colorectal cancer

• Infectious colitis, eg, Campylobacter, Clostridioides difficile

• Inflammatory bowel disease

• Ischemic colitis

• Appendicitis

• Gynecologic

  • Ovarian cyst or torsion

  • Ectopic pregnancy

• Urinary calculus

• Gastroenteritis

Diagnosis

Laboratory Tests

• Leukocytosis, mild to moderate

• Stool occult blood test positive, but hematochezia is rare

Imaging Studies

• Endoscopy and colonography are contraindicated during the initial stages of an acute attack because of the risk of free perforation

• Perform radiologic imaging (CT colonography or barium enema) only after resolution of clinical symptoms to document extent of diverticulosis or presence of fistula

• CT scan of the abdomen indicated

  • In patients who do not improve rapidly after 2–4 days of empiric therapy

  • In those with fever, leukocytosis, and sepsis or peritonitis

  • In those who are immunocompromised to look for evidence of complicated disease

  • When presence of colonic diverticula and wall thickening, pericolic fat infiltration, abscess formation, or extraluminal air or contrast suggests diagnosis

  • In those who do not improve after 72 hours of medical management

Diagnostic Procedures

• Colonoscopy

  • Recommended in patients over age 50 who have not undergone appropriate screening

  • Should be considered in other high-risk patients, especially those with suspicious radiologic imaging, diverticulitis with complications or protracted symptoms, or family history of colorectal cancer

  • Contraindicated during acute attack

  • Perform only after resolution of clinical symptoms to document extent of diverticulitis and to exclude other clinical disorders

Treatment

Medications

• Most patients can be managed with conservative measures

• Mild diverticulitis (mild symptoms and no peritoneal signs)

  • Clear liquid diet

  • Antibiotics should be used selectively for uncomplicated disease (immunocompromised, significant comorbid disease, small pericolonic abscess)

  • Broad-spectrum oral antibiotics with anaerobic activity, such as amoxicillin and clavulanate potassium, 875 mg/125 mg twice daily orally; or metronidazole, 500 mg three times daily ...