Summary: 

Diverticula are sac-like protrusions of the colonic wall that tend to occur at increasing rates with older age, with an estimated 50% of adults over the age of 60 developing diverticula. Diverticulosis is defined as the presence of diverticula, and 5 to 10% of patients with diverticulosis will go on to develop symptomatic disease such as diverticulitis, recurrent pain, and bleeding. Following an episode of diverticulitis, a recurrence will occur in 8% to 36% of patients at 1 to 10 years. Additionally, patients who present with complicated diverticulitis – or diverticulitis associated with abscess, bleeding, obstruction, fistula or perforation – have a higher prevalence of colorectal cancer that may be misdiagnosed or missed on initial imaging.  The ACP has put together recommendations regarding follow up care after an episode of left-sided diverticulitis given these increased risks.  

Definitions: 

Uncomplicated Diverticulitis 

• Left lower quadrant abdominal pain and change in bowel habits associated with localized inflammation of diverticula 
• No signs or symptoms of sepsis  
• Immunocompetent patients  

Complicated Diverticulitis  

• Diverticulitis with at least one of the following: Perforation | Bleeding | Obstruction | Abscess/Phlegmon | Fistula | Immunosuppressed patient  

Colonoscopy for Diagnostic Evaluation: 

“ACP suggests that clinicians refer patients for a colonoscopy after an initial episode of complicated left-sided colonic diverticulitis in patients who have not had recent colonoscopy” 

• Evidence is inconclusive on whether there is a net benefit in obtaining colonoscopy following uncomplicated diverticulitis  
• Evidence is also inconclusive on whether there is improved CRC mortality with colonoscopy following complicated diverticulitis  
• Despite this, ACP recommends colonoscopy following complicated diverticulitis in patients with no recent colonoscopy to rule out CRC given that CRC may present with similar signs and symptoms to complicated diverticulitis  

• Colonoscopy should be obtained at least 6 to 8 weeks after resolution of diverticulitis  
• ACP does not define “recent colonoscopy”, but they do not recommend colonoscopy for patients who are otherwise up to date on their CRC screening  
• Colonoscopy may be most beneficial for those at higher risk of CRC: Older age | Malnutrition | Weight loss | Change in bowel habits | Bloody stool | Persistent abdominal pain  

Interventions to Prevent Recurrence: 

“ACP recommends against clinicians using mesalamine to prevent recurrent diverticulitis” 

• Diverticulitis is believed to be an inflammatory process, so there was interest in using anti-inflammatory medications to prevent recurrence 
• Studies reviewed showed no benefit and more discontinuation of drug due to adverse events with mesalamine use  

Dietary Interventions 

• ACP did not review studies on dietary therapies (e.g. high fiber diet) for reduction of recurrent diverticulitis  

• A large study in 2008 demonstrated no increased risk for diverticulitis with a diet including nuts, corn, and popcorn, despite the persistence of this belief in the medical community (see  
  Primary Sources – Learn More below)  

“ACP suggests that clinicians discuss elective surgery to prevent recurrent diverticulitis after initial treatment in patients who have either uncomplicated diverticulitis that is persistent or recurs frequently or complicated diverticulitis. The informed decision whether to undergo surgery should be personalized based on a discussion of potential benefits, harms, costs, and patient’s preferences” 

• Elective surgery should not be offered to patients with uncomplicated diverticulitis that is not persistent or recurring  
• Discussion of surgery should include potential harms as 1.4% to 5.5% of surgical patients develop post-op complications (e.g. anastomotic leak, sepsis, MI)  
• There is no minimum number of recurrences necessary for surgery and discussion should be tailored to the individual patient  

• Evidence did show decreased rate of recurrent diverticulitis with surgery for patients with: 
  • Complicated or uncomplicated diverticulitis with long term symptoms following acute episode (> 3 months of symptoms)  
  • Complicated or uncomplicated diverticulitis with high rate of recurrence (> or = 3 over 2 years)  

Primary Sources – Read More  

Colonoscopy for Diagnostic Evaluation and Interventions to Prevent Recurrence After Acute Left-Sided Colonic Diverticulitis: A Clinical Guideline From the American College of Physicians 

Nut, corn, and popcorn consumption and the incidence of diverticular disease