What is the diagnosis and treatment for diverticulitis (inflammation of the diverticula)?

From the Guidelines

Diverticulitis should be diagnosed using abdominal CT imaging when there is diagnostic uncertainty, and most patients with acute uncomplicated left-sided colonic diverticulitis can be managed in an outpatient setting without antibiotics. The diagnosis of diverticulitis typically involves a detailed history, physical examination, and laboratory findings, with abdominal CT imaging used to complement these findings when diagnostic uncertainty remains 1. The management of diverticulitis depends on the severity of the condition, with mild cases often treated with oral antibiotics and a liquid or low-fiber diet, while more severe cases may require hospitalization for intravenous antibiotics, pain management, and possibly surgical intervention if complications like perforation, abscess, or obstruction occur. Some key points to consider in the management of diverticulitis include:

• The use of abdominal CT imaging to diagnose diverticulitis, particularly when diagnostic uncertainty remains 1
• The management of most patients with acute uncomplicated left-sided colonic diverticulitis in an outpatient setting without antibiotics 1
• The use of antibiotic treatment selectively, rather than routinely, in immunocompetent patients with mild acute uncomplicated diverticulitis 1
• The importance of maintaining a high-fiber diet, staying well-hydrated, exercising regularly, and avoiding NSAIDs when possible to prevent recurrence 1
• The need for immediate medical attention if severe abdominal pain, fever, or inability to pass gas or stool occur, as these may indicate serious complications. In terms of specific treatment options, some studies suggest that:
• Patients with small diverticular abscesses (< 4-5 cm) can be treated with antibiotic therapy alone 1
• Patients with large diverticular abscesses should be treated with percutaneous drainage combined with antibiotic treatment 1
• The size of the abscess is an important factor in determining the best treatment approach, with larger abscesses requiring more aggressive treatment 1. Overall, the management of diverticulitis requires a comprehensive approach that takes into account the severity of the condition, the patient's overall health, and the potential risks and benefits of different treatment options.

From the Research

Diagnosis and Classification of Diverticulitis

• Radiological evidence of inflammation, using computed tomography (CT), is needed to diagnose the first occurrence of diverticulitis 2
• CT is also warranted when the severity of symptoms suggests that perforation or abscesses have occurred 2
• Diverticulitis is classified as complicated or uncomplicated based on CT scan, severity of symptoms and patient history; this classification is used to direct management 2

Treatment of Uncomplicated Diverticulitis

• Outpatient treatment is recommended in afebrile, clinically stable patients with uncomplicated diverticulitis 2
• Antibiotics have no proven benefit in reducing the duration of the disease or preventing recurrence, and should only be used selectively 2, 3
• A systematic review found that there may be little or no difference between antibiotics and no antibiotics in terms of short-term complications 3
• The rate of emergency surgery within 30 days may be lower with no antibiotics compared to antibiotics, but the evidence is uncertain 3

Treatment of Complicated Diverticulitis

• Non-operative management, including bowel rest and intravenous antibiotics, is indicated for small abscesses 2
• Larger abscesses of 3-5 cm should be drained percutaneously 2
• Patients with peritonitis and sepsis should receive fluid resuscitation, rapid antibiotic administration and urgent surgery 2
• Surgical intervention with either Hartmann procedure or primary anastomosis, with or without diverting loop ileostomy, is indicated for peritonitis or in failure of non-operative management 2

Role of Antibiotics in Diverticulitis

• Antibiotics play a key role in the management of both uncomplicated and complicated diverticulitis 4
• Rifaximin has demonstrated to be effective in obtaining symptoms relief at 1 year in patients with uncomplicated diverticulitis 4
• Conservative treatment with broad-spectrum antibiotics is successful in up to 70% of cases of abscesses 4
• The evidence on antibiotic treatment for uncomplicated acute diverticulitis suggests that the effect of antibiotics is uncertain for complications, emergency surgery, recurrence, elective colonic resections, and long-term complications 3