Diverticula: what are the symptoms of diverticulitis and how to treat it

By Cristiano Antonino Last updated Oct 20, 2022

Diverticula are extroversions of the mucosa and submucosa comparable to small pockets, which can form in the digestive tract, but their most frequent location is on the intestinal wall at the level of the colon

Diverticulosis, diverticular disease and diverticulitis: what are the differences?

As already mentioned, diverticula are extroversions of the mucosa and submucosa (thus, they are actually pseudo-diverticula) comparable to small protruding pockets that can form in various places in the digestive tract, but most often develop at the level of the intestinal wall of the colon.

In particular, the wall of the colon consists of four layers, which starting from the inside are mucosa, submucosa, muscular tonaca and serous tonaca.

The process of diverticulum formation occurs when the two innermost layers of the wall, i.e. mucosa and submucosa, make their way, adjacent to the entry points of the small blood vessels that irrigate the wall itself, to protrude into the abdominal cavity.

A distinction is generally made between:

diverticulosis: present in less than 10% of individuals under 40 years of age, and in more than 50% of individuals over 60 years of age, it is characterised by the asymptomatic presence of diverticula; in 80% of cases, these are discovered by chance during a colonoscopy, ultrasound or other abdominal X-ray examination performed for other reasons. In Western populations they are mainly located in the left colon (>95% in the sigma), whereas in Asian populations they are more frequent in the right colon;
symptomatic uncomplicated diverticular disease: up to 15% of diverticulosis sufferers may report symptoms such as bloating, abdominal pain (especially in the lower left abdomen) and altered bowel regularity, which are superimposed on those of irritable bowel syndrome;
diverticular disease with acute diverticulitis: up to 5-10% of diverticulosis sufferers may develop infection/inflammation of the diverticula leading to symptoms such as severe and prolonged abdominal pain, associated with constipation/diarrhoea, meteorism, nausea, decreased appetite, and accompanied by fever. It can be further subdivided into uncomplicated diverticulitis (circumscribed infection/inflammation) and complicated diverticulitis (associated with abscess, peritonitis or bleeding);
segmental colitis associated with diverticulosis: a small percentage of individuals with diverticulosis may develop a localised inflammatory process in the colon mucosa between the diverticula, with endoscopic and histological features similar to those of chronic inflammatory bowel disease.

What are the causes of diverticula?

Colonic diverticula represent a rather widespread anatomical alteration, the formation of which can be favoured by

genetic predisposition, as has recently emerged in twin concordance studies and association studies that have identified certain gene variants associated with diverticular disease;
age, especially after the age of 40, because as we age, the connective tissue that supports the intestine becomes more lax;
male gender;
poor eating habits (e.g. low-fibre diet);
obesity;
sedentary lifestyle;
intake of anti-inflammatory drugs (such as steroid and non-steroid anti-inflammatory drugs);
chronic constipation, which leads to increased internal pressure on the walls of the colon.

What tests should be done for diagnosis?

The presence of diverticula can be diagnosed through the following examinations

traditional colonoscopy;
abdominal CT scan;
virtual colonoscopy, which is nothing more than an abdominal CT scan with three-dimensional reconstruction of the colon; this allows accurate observation of the internal intestinal wall in a non-invasive manner, without inserting an endoscopic probe into the intestine;
double-contrast opaque schism.

What to do in case of diverticulosis or uncomplicated diverticular disease?

In the presence of diverticula, even in the absence of symptoms, it is generally recommended to undergo an annual gastroenterological check-up.

Following the diagnosis of diverticulosis or symptomatic uncomplicated diverticular disease, the patient is not usually required to follow a particular diet, although it is generally recommended to increase the intake of water, cereals, fruit and vegetables, and possibly also using soft faecal mass-forming substances (e.g. psyllium or macrogol), so as to increase the intake of fibre (at least 30 grams per day) and thus reduce the internal pressure in the colon (anti-spastic drugs are also useful for this), promote intestinal motility and combat constipation.

Periodic treatments based on antibiotic or anti-inflammatory bowel therapy, or probiotics may be of some benefit in reducing intestinal symptoms, but not the frequency of diverticulitis.

How is diverticulitis treated?

In the case of acute diverticulitis, however, hospitalisation may be necessary: in most cases, however, the problem is resolved without surgery (reserved for cases that develop complications or repeated attacks of acute diverticulitis).

The gastroenterologist generally proposes first of all a diet that puts the intestine at rest, avoiding vegetable fibres for a few days, preferring a more liquid diet or in any case one that combines carbohydrates and proteins above all with the right hydration.

The diet is then generally combined with antibiotic therapy.

Can diverticula be prevented?

A correct lifestyle can help reduce the risk of diverticulum formation.

In particular, it is advisable to favour a diet rich in fibre and low in saturated fats, to counteract possible constipation, and to ensure one’s body has the right amount of water (during meals or immediately afterwards), to promote intestinal peristalsis, i.e. the movements that induce the expulsion of stools.