Diverticular Disease and Diverticulitis

🧭 When to suspect

Diverticular disease sits on a spectrum, and naming the right point on it drives everything that follows. Diverticulosis is the presence of diverticula without symptoms – common with age and usually found incidentally; around 80–85% of affected people stay asymptomatic. Diverticular disease is symptomatic diverticula with mild pain or tenderness but no systemic upset. Acute diverticulitis is when diverticula become inflamed or infected, and complicated disease is diverticulitis with an abscess, perforation, fistula, stricture or sepsis.

Suspect diverticular disease in a person (usually over 50) with intermittent left lower quadrant (LLQ) pain alongside constipation, diarrhoea or occasional large rectal bleeds – the pain is often triggered by eating and relieved by passing stool or flatus – or with LLQ tenderness on examination. Suspect acute diverticulitis when the pain becomes constant and severe in the LLQ with fever, a sudden change in bowel habit with significant rectal bleeding or mucus, or a tender LLQ mass in someone with known diverticula.

Two questions then run through the whole consultation: is the person systemically well, and are there any features of complicated disease? Be aware symptoms overlap with IBS, colitis and colorectal cancer, and that in a minority – and in people of Asian family origin – pain may localise to the right lower quadrant.

Source: NICE NG147