Diverticulitis: Questioning Current Practice
- Before effective treatments including broad spectrum antibiotics, diverticulitis was a disease with high morbidity and mortality.
- Standard of care has been antibiotics (for complicated or uncomplicated diverticulitis), and often surgery for patients with multiple recurrences.
- Meta-analysis1 by Morris et al in JAMA in 2014 looks at current practices and asks:
- What is the known pathophysiology – how do diverticula become inflamed and what are risk factors?
- What is the natural history, when managed non-operatively?
- What are medical treatment options (current and future)?
- What are the indications for surgery?
- Certain advances have changed the thinking about diverticulitis:
- CT can distinguish complicated (perforation, abscess, phlegmon) from uncomplicated diverticulitis
- Better follow-up in large populations has allowed for better understanding of natural history
- Similarities found in pathophysiology among diverticulitis, inflammatory bowel disease, and irritable bowel syndrome
- Surgeons pursuing less invasive management.
- Authors looked at articles from 2000-2013.
- Found 1383 abstracts and articles, narrowed to 186.
- Prevailing theory for the formation of diverticula is that “altered bowel motility leading to increased luminal pressures causes mucosal outpouching.”
- “Recurrent or chronic diverticulitis displays chemical and histological similarities to inflammatory bowel disease and irritable bowel syndrome.”
- High levels of histamine, TNF-alpha, and matrix metalloproteinases, as well as granulomas and infiltrating lymphocytes found in all 3 diseases (although unable to show a common pathway).
- Lower risk for diverticular disease among vegetarians compared to meat eaters (RR 0.69 [95%CI 0.55-0.86]).
- Despite common beliefs, one study showed highest level of diverticulosis among those with the highest fiber intake, and another study showed no relation to nut, corn or popcorn ingestion.
- Diverticulitis risk increased with smoking and obesity, and decreased with physical activity.
- Perforation risk increased with NSAIDs, opioids, and corticosteroids.
- Recurrence is relatively rare and usually benign.
- Complications usually during first episode, not during recurrent episodes.
- Goals: Decrease acute inflammation, prevent recurrence, and manage chronic symptoms
- Some studies support use for preventing recurrence, others showed no benefit. Most had poor quality evidence.
- 4 studies look at fiber alone vs rifaximin + fiber: rifaximin + fiber had a slight benefit in symptom relief and preventing complications
- A Cochrane review did not support use of antibiotics in acute uncomplicated diverticulitis.
- Good studies have shown no benefit of IV over PO antibiotics, and equal effect of 4-day vs 7-day courses.
- Another systematic review and a retrospective cohort study found that antibiotics did not improve complication rate, need for surgery, or recurrence rate.
- Thought that deranged colonic microenvironment contributes to chronic inflammation, so theoretical benefit of probiotics.
- Prospective trial of 83 patients found probiotics after first episode led to less bloating, pain and fever, but equal recurrence rates.
- Study comparing the anti-inflammatory medication, mesalamine, with the antibiotic, rifaximin, found significantly reduced symptoms after 6-12 months with mesalamine.
Role of surgery
- Current indications: Sepsis and peritonitis on presentation, or failure to improve with medical therapy or percutaneous drainage. Often done in patients with recurrence to prevent complications or emergent surgery.
- Recurrent diverticulitis – Questioning the need for surgery:
- Complicated recurrence in only 5% who recovered from uncomplicated diverticulitis
- Risk of future emergent surgery after uncomplicated diverticulitis was only 4-7%
- Multiple recurrences did not increase risk of major complications
- Complications most commonly during first episode
- 5-25% of patients who underwent surgery had recurrent/unresolved symptoms afterwards anyway
- Surgery can miss the location of future episodes
- Recent studies suggest a lesser role for aggressive antibiotic and surgical treatments in diverticulitis, and newer treatments such as anti-inflammatory medications (mesalamine) and perhaps probiotics have shown some benefit. However, future research is needed in this area to change the current dogma.
- Morris AM, Regenbogen SE, Hardiman KM, Hendren S. Sigmoid diverticulitis: a systematic review. JAMA Surg. 2014;311:287–297.