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

  • Pelvic inflammatory disease

  • Tubo-ovarian abscess

  • Ovarian cyst or torsion

  • Ectopic pregnancy

  • Mittelschmerz

  • Endometriosis

• Urinary calculus

• Gastroenteritis

Diagnosis

Laboratory Tests

• Leukocytosis, mild to moderate

• Stool occult blood test positive, but hematochezia is rare

Imaging Studies

• Indications for CT scan of the abdomen

  • Suspected diverticulitis, especially in patients with fever, leukocytosis, and signs of sepsis or peritonitis

  • Evidence of complicated disease in immunocompromised patients

  • Presentation of mild symptoms for first time to look for evidence of diverticulitis (colonic diverticula, wall thickening, pericolic fat infiltration) and to exclude other causes of abdominal pain

• Patients who respond to acute medical management should undergo complete colonic evaluation with colonoscopy or radiologic imaging CT colonography) 4–8 weeks after resolution of clinical symptoms to exclude colorectal cancer (which may mimic diverticulitis)

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

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 with uncomplicated disease can be managed with conservative measures

• Mild diverticulitis (mild symptoms and no peritoneal signs)

  • Clear liquid diet for 2–3 days

  • 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 orally; plus either ciprofloxacin, 500 mg twice ...