Diagnosing and managing acute diverticulitis.

Diverticulosis is the most common structural abnormality of the colon and affects up to one third of those over the age of 60 years. Its complications account for more than 3,000 deaths per year. Acute diverticulitis is the most common complication and 10-25% of patients with diverticulosis may have one or more episodes. Patients present with left-sided abdominal pain that localises in the left iliac fossa. This left-sided pain reflects the underlying predominant left-sided distribution of the diverticula on this side. Patients may also present with right-sided or suprapubic pain, caused either by right-sided diverticulosis or a redundant sigmoid loop lying toward the right side, which may mimic appendicitis. The pain may be associated with changes in bowel habit. Dysuria and frequency may occur if the inflamed segment of bowel is adjacent to the bladder. Patients should be assessed according to their level of pain and associated systemic features of sepsis. In those in whom the pain is controlled and there are no signs of systemic sepsis and no high-risk features the patient may be treated in primary care but for those with systemic features of sepsis or high-risk features admission to hospital is required. The diagnosis of acute diverticulitis in all patients with a new presentation should be confirmed by CT scan on admission to hospital.