Clinical presentation and risks

A recurrent episode of diverticulitis is a new distinct episode of acute inflammation after a period of complete remission of symptoms. Outdated literature suggested a high recurrence rate (>40%) and a worse clinical presentation with less chance of conservative treatment. More recent studies showed a more benign course with no need toward an aggressive policy of treatment.

We report data from revised literature and from our study: a 4-year multicenter retrospective and prospective database analysis of 743 patients hospitalized for acute diverticulitis (AD) treated medically or surgically and then followed for a minimum of 9 years.

The literature showed a recurrence rate of 25-35% at 5 years of follow-up, with a reduced risk of severe complications (i.e. perforations), a risk of subsequent emergency surgery of 2-14% and a risk of stoma and related death of 0-2.7%. Several risk factors of recurrence have been advocated: family history, abscess, severe CT stage, comorbidities (renal failure, collagen vascular disease) and nonsteroidal anti-inflammatory drugs. Young age is still a matter of debate. These studies have different limitations: retrospective, lack of definition of AD, small number of patients, long recruiting time, short follow-up, study population or hospital-system based. In our study of 320 followed-up, medically treated patients, 61% were asymptomatic and 22% complained of chronic symptoms: the 12-year actuarial risk of recurrence, emergency surgery, stoma and death was 21.2, 8.3, 1 and 0%, respectively. Recurrence was related to very young age (<40 years) and more than 3 previous episodes of AD.

This study confirms the benign course of diverticulitis treated conservatively, with a low long-term risk of serious complications and death, and does not support an aggressive surgical policy to prevent them.