What is the most appropriate management for a middle-aged man with hypertension, managed with medication, presenting with nausea, lack of appetite, diarrhea, and cramping pain in the right lower abdomen, tenderness to palpation, elevated white blood cell count, and thickening of the colon on CT scan?

Management of Acute Right Lower Quadrant Diverticulitis

This patient should be admitted to the hospital for intravenous antibiotics, bowel rest, and close monitoring, as he presents with acute right-sided colonic diverticulitis confirmed by CT imaging with systemic signs of infection (elevated WBC count). 1

Clinical Presentation and Diagnosis

This patient's presentation is consistent with uncomplicated acute colonic diverticulitis based on:

• Right lower quadrant pain with tenderness on palpation but no peritoneal signs (no rigidity or rebound) 1
• Elevated white blood cell count indicating inflammatory response 1
• CT findings of colonic wall thickening consistent with diverticulitis 1
• Absence of complications such as abscess, perforation, or distant free air 1

The WSES classification categorizes this as Stage 0 (uncomplicated) diverticulitis: diverticula with wall thickening and increased pericolic fat density without abscess or free air. 1

Why Hospital Admission is Required

Admission is strongly recommended rather than outpatient management because:

• The patient has systemic signs of infection with elevated WBC count, indicating the inflammatory process extends beyond localized disease 1
• He has been symptomatic for two days with ongoing symptoms (nausea, lack of appetite, diarrhea), suggesting failure of the body to contain the infection spontaneously 1
• CT confirmation is present, which allows for accurate staging and monitoring for potential complications 1
• The 2021 AGA guidelines emphasize that patients with confirmed diverticulitis and systemic inflammatory markers warrant closer observation to detect clinical deterioration 1

Inpatient Management Protocol

Immediate Interventions:

• Complete bowel rest (NPO initially, then clear liquids as tolerated) for 2-6 days 1
• Broad-spectrum intravenous antibiotics covering gram-negative and anaerobic organisms for 3-5 days 1
• Intravenous hydration to maintain adequate perfusion and support the inflammatory response 1
• Serial abdominal examinations every 6-12 hours to detect development of peritoneal signs 1

Monitoring Parameters:

• Daily clinical assessment for worsening pain, development of peritoneal signs, or hemodynamic instability 1
• Repeat inflammatory markers (WBC, CRP) at 48-72 hours to assess treatment response 1
• Vital signs monitoring for fever, tachycardia, or hypotension suggesting progression to complicated disease 1

Why Other Options Are Inappropriate

Bedrest with clear liquid diet at home is insufficient because:

• This approach lacks the monitoring capability to detect complications such as abscess formation or perforation 1
• The patient has systemic inflammation requiring IV antibiotics, which are more effective than oral agents in acute diverticulitis 1

High-fiber diet recommendation is contraindicated in acute diverticulitis:

• High-fiber foods should be avoided during the acute phase as they increase colonic motility and intraluminal pressure 1
• Fiber supplementation is only appropriate after complete resolution of acute symptoms, typically 6-8 weeks later 1

Immediate surgical referral or therapeutic procedure is not indicated because:

• This is uncomplicated diverticulitis without abscess, perforation, obstruction, or fistula 1
• Surgery is reserved for complicated disease (abscess >4-6 cm, perforation with peritonitis, obstruction) or recurrent episodes after failed medical management 1
• The 2020 WSES guidelines clearly state that uncomplicated diverticulitis should be managed conservatively with antibiotics and bowel rest 1

Critical Pitfalls to Avoid

• Do not discharge patients with systemic signs of infection (elevated WBC, fever) for outpatient management, as they require monitoring for progression to complicated disease 1
• Do not delay admission in patients with confirmed CT findings and inflammatory markers, as early intervention prevents progression to abscess or perforation 1
• Do not perform colonoscopy during the acute phase, as this increases perforation risk; defer colonoscopy for 6-8 weeks after symptom resolution to exclude malignancy 1

Expected Clinical Course

• Most patients with uncomplicated diverticulitis respond to conservative management within 48-72 hours, with improvement in pain and normalization of inflammatory markers 1
• Transition to oral antibiotics and diet advancement should occur once the patient is afebrile, pain is improving, and he tolerates oral intake 1
• Total antibiotic duration is typically 7-10 days (IV + oral) 1
• Hospital length of stay averages 3-5 days for uncomplicated diverticulitis managed conservatively 1

Follow-up Requirements

• Colonoscopy at 6-8 weeks after complete symptom resolution to exclude underlying malignancy, as colon cancer can mimic diverticulitis (1.3% prevalence in uncomplicated cases) 1
• Dietary counseling after recovery to increase fiber intake gradually to 25-30 grams daily to prevent recurrence 1
• Outpatient follow-up in 2-4 weeks to assess complete resolution and discuss long-term management strategies 1