What is the most appropriate initial management for an elderly patient with diverticulosis (diverticula disease) presenting with mild intermittent left lower abdominal pain, no fever, normal white blood cell count (WBCs), and no signs of peritonitis?

Initial Management: CT Abdomen with IV Contrast

The most appropriate initial management for this elderly patient is CT abdomen and pelvis with IV contrast (Option A), as this is essential to confirm the diagnosis and distinguish between uncomplicated diverticulosis, acute diverticulitis, and other serious pathology that commonly mimics diverticular disease in the elderly.

Rationale for CT Imaging First

The 2022 WSES/SICG guidelines specifically recommend CT scan with IV-contrast in all elderly patients with suspected diverticulitis regardless of WBC count or inflammatory markers to confirm diagnosis and distinguish complicated from uncomplicated disease 1. This is critical because:

• Diagnostic difficulty in elderly patients: Among patients >80 years presenting with acute abdominal pain, the clinical diagnosis was clinically unsuspected prior to CT in 43% of cases, with significant difficulty diagnosing diverticulitis 1
• CT influences treatment plans: CT results influenced treatment decisions in 65% of elderly patients overall (48% surgical, 52% medical management) 1
• High sensitivity and specificity: CT demonstrates 95% sensitivity and 96-99% specificity for diverticular disease 1
• Excludes other diagnoses: The elderly have multiple competing diagnoses including ischemic colitis, malignancy, and inflammatory bowel disease that require different management 1

Why Not the Other Options?

Option B (IV Antibiotics and Bowel Rest) - Premature

• Cannot assume acute diverticulitis without imaging: This patient has diverticulosis (structural finding), not confirmed diverticulitis (inflammatory process) 1
• Antibiotics may not be necessary: Even in confirmed uncomplicated acute diverticulitis, recent evidence suggests antibiotics may not be required in mild-moderate cases 2, 3
• Risk of missing serious pathology: Without CT, you could miss perforation, abscess, malignancy, or ischemia that require different interventions 1, 4

Option C (Increase Fiber and Fluid) - Inappropriate Timing

• Not for acute symptoms: While fiber may be recommended for general health, there is little evidence it benefits recovery during acute episodes 2
• Diagnosis must be established first: You cannot treat symptomatically without excluding serious pathology in an elderly patient with new abdominal pain 1, 4
• May worsen certain conditions: If obstruction or acute inflammation is present, increasing fiber could exacerbate symptoms 5

Option D (Laparotomy) - Grossly Premature

• No indication for surgery: This patient has no fever, normal WBCs, and no peritonitis—all reassuring signs 1
• Surgery reserved for complications: Laparotomy is indicated for diffuse peritonitis (WSES stage 3-4), which this patient does not have 1

Clinical Algorithm

Step 1: Obtain CT abdomen/pelvis with IV contrast immediately 1

• Do not let chronic kidney disease discourage contrast use in elderly patients, as prompt diagnosis justifies the minimal risk of contrast-induced acute kidney injury 1
• Recent meta-analyses show no increased CI-AKI risk in CKD patients receiving IV contrast for CT 1

Step 2: Based on CT findings, proceed as follows:

• If uncomplicated diverticulitis confirmed: Consider outpatient management without antibiotics if patient is immunocompetent and clinically stable 2, 3
• If complicated diverticulitis (abscess, perforation): Admit for IV antibiotics, possible percutaneous drainage, or surgery 1
• If alternative diagnosis found: Manage accordingly (malignancy, ischemia, IBD) 1, 4
• If only diverticulosis without inflammation: Consider symptomatic management and colonoscopy if not done within 3 years to exclude malignancy 2

Critical Pitfalls to Avoid

• Do not treat empirically without imaging in elderly patients: The differential diagnosis is broad and missing serious pathology carries high mortality 1, 4
• Do not assume "mild" symptoms mean benign disease: Elderly patients may have blunted inflammatory responses and present atypically even with serious pathology 6
• Do not perform colonoscopy during acute symptoms: This increases perforation risk; defer colonoscopy at least 6 weeks after acute episode 2