Imaging and Workup for Acute Diverticulitis and Diverticular Bleeding in Adults > 50 years

Initial Imaging for Suspected Acute Diverticulitis

When a patient presents with left‑lower‑quadrant pain, fever, and leukocytosis, immediate cross‑sectional imaging is recommended.

Alternative Imaging Modalities

Imaging for Diverticular Bleeding

Post‑Acute Episode Colonoscopic Evaluation

Disease Severity Classification (WSES Staging)

Management of Sigmoiditis

Diagnosis and Initial Management

• The American College of Gastroenterology recommends confirming sigmoiditis through CT scan with intravenous contrast, which differentiates between uncomplicated and complicated forms with a sensitivity of 98-99% and specificity of 99-100% 7
• Uncomplicated sigmoiditis is defined as localized inflammation without abscess, perforation, fistula, obstruction, or bleeding, while complicated sigmoiditis involves the presence of abscess, perforation, fistula, obstruction, or diffuse peritonitis 8, 7

Management of Uncomplicated Sigmoiditis

• The majority of immunocompetent patients with uncomplicated sigmoiditis can be treated as outpatients without antibiotics, with simply bowel rest, clear liquid diet, and pain control with paracetamol 8
• Antibiotics should be reserved for patients with specific risk factors, such as immunocompromised status, age >80 years, pregnancy, significant comorbidities, or high ASA score 8
• Recommended antibiotic regimens for uncomplicated sigmoiditis include ciprofloxacin 500 mg PO 2×/day plus metronidazole 500 mg PO 3×/day, or amoxicillin-clavulanate 875/125 mg PO 2×/day 8

Management of Complicated Sigmoiditis

• Complicated sigmoiditis, including abscess, perforation, or peritonitis, requires urgent surgical consultation and control of the source 9, 10
• Antibiotics should be started promptly, with regimens including ceftriaxone plus metronidazole, or piperacillin-tazobactam 8, 9
• Surgical options include resection with anastomosis, Hartmann procedure, or damage control surgery, depending on the patient's stability and the extent of the disease 9, 7

Hospitalization vs Ambulatory Care

• Hospitalization is mandatory for patients with complicated sigmoiditis, inability to tolerate oral intake, systemic inflammatory response, or significant comorbidities 8, 9
• Ambulatory care is appropriate for patients who can tolerate oral liquids and medications, have no significant comorbidities, and have adequate home support 8

Follow-up and Re-evaluation

• Re-evaluation is obligatory within 7 days, or sooner if there is clinical deterioration 8
• A follow-up CT scan is necessary if symptoms persist after 5-7 days of antibiotic therapy to evaluate for complications requiring drainage or surgery 8
• Colonoscopy is recommended 4-6 weeks after resolution to exclude colorectal neoplasia, particularly after complicated sigmoiditis or first episode in patients >50 years old 8, 7

Prevention of Recurrences

• Lifestyle modifications, including a high-fiber diet, regular physical activity, maintenance of a normal BMI, smoking cessation, and avoidance of non-aspirin NSAIDs, are strongly recommended to prevent recurrences 8
• There is no evidence to support the restriction of nuts, corn, popcorn, or small-seeded fruits, or the use of mesalazine or rifaximin for prevention 8

Elective Surgical Considerations

• Elective resection should not be based solely on the number of episodes, but rather on the impact on quality of life, frequency of recurrences, and patient preferences 8
• Indications for elective resection include ≥3 confirmed episodes in 2 years, persistent symptoms >3 months, complications, or significant impact on quality of life 8, 9