Diverticulosis
Diverticulosis is the acquired presence of uninflamed mucosal and submucosal herniations through the colonic wall, overwhelmingly asymptomatic and usually found incidentally on colonoscopy or CT, that serves as the anatomic substrate for diverticulitis and diverticular bleeding rather than a disease in itself. Management of uncomplicated diverticulosis is a high-fiber diet with no restriction of nuts, seeds, or popcorn, plus routine age-based colorectal cancer screening.
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What this article covers
- Overview
Definition: diverticulosis is the mere presence of diverticula, acquired herniations of the mucosa and submucosa through a weakness in the colonic muscular wall, without inflammation.
- Epidemiology
Age-dependent prevalence: uncommon before age 40 years, then increases progressively with age, reaching a reported prevalence of about 80% by the ninth decade.
- Risk factors
Low-fiber, high-fat diet: the classic dietary driver, historically described as a low-fiber, high-fat, low-residue diet.
- Pathophysiology
Structural weakness at vasa recta penetration sites: the vasa recta (the arteries supplying the colonic mucosa) pierce the circular muscle layer at regular intervals, creating natural points of relative weakness in the wall.
- Clinical features
Asymptomatic in the large majority: most patients have no symptoms attributable to diverticulosis and are unaware they have it.
- Differential diagnosis
Diverticulitis: distinguished by fever, leukocytosis, and localized left lower quadrant tenderness or a palpable mass from active inflammation, versus the asymptomatic, normal examination of diverticulosis (Diverticulitis).
- Diagnosis
Diverticulosis is confirmed by direct visualization on colonoscopy or by cross-sectional or contrast imaging (CT or barium enema), typically as an incidental finding rather than through a formal…
- Management
No treatment is required for asymptomatic diverticulosis itself: because it is an anatomic finding rather than an active disease process, management is limited to risk reduction for future complications and routine cancer surveillance.
- Complications
Diverticulitis: inflammation or microperforation of a diverticulum from obstruction and bacterial trapping, presenting with left lower quadrant pain, fever, and leukocytosis; the most frequent complication (Diverticulitis).
- Prognosis
Excellent for uncomplicated diverticulosis: the great majority of patients remain asymptomatic for life and require no disease-specific treatment.
- Prevention
High-fiber diet to reduce complication risk: sustained increase in dietary fiber intake (fruits, vegetables, whole grains, legumes, with a fiber supplement such as psyllium when intake remains…
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Diverticulitis is inflammation and micro- or macro-perforation of a colonic diverticulum, most often sigmoid, presenting with left lower quadrant pain, fever, and altered bowel habits. CT abdomen and pelvis with contrast confirms the diagnosis, separates uncomplicated from complicated disease, and grades complicated disease by the modified Hinchey classification to guide antibiotics, drainage, or surgery.
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