Diverticulitis Latest Facts: Causes, Risk Factors, Diagnosis and Treatment

What is Diverticulitis?

Diverticulitis is an inflammation and infection of abnormal pouches in the colon, which are called diverticulums. The presence of diverticula in the large intestine is known as diverticulosis. Diverticulosis itself does not cause many symptoms, but when these outpouchings become infected, they can cause severe pain.

Abdominal Pain

Diverticulitis is one of the common disorders affecting the digestive tract in the West, affecting almost 35% of the US population under the age of 50, and 58% of the population over the age of 60 years. Furthermore, around 20% of patients with diverticulitis have a 1% recurrence rate. Diverticulitis is more common in men than women until the 6th decade of life, where it becomes more common in women.

What are the causes and risk factors of Diverticulitis?

The exact cause for diverticulitis or diverticular disease is not known but researches show a high contribution of environmental factors in the development and progression of diverticular disease.

Diverticulosis develops due to weakness in the colonic wall resulting in an outpouching of the colon. Multiple diverticula can be present in a patient without any symptoms.

Diverticulitis, on the other hand, is hypothesized to develop due to higher pressures within the colon, associated with vigorous contractions. It is also associated with many risk factors, such as:

Age: Older people are more likely to develop diverticulitis than young people. It usually affects men younger than 50 years of age, and women between the ages of 50 and 70 years.
Family history: It contributes to the development of diverticulitis in about 40% of total cases.
Low fiber diets: While some studies have shown a connection between a low fiber diet and diverticulitis, others have failed to find it. Hence, it is not confirmed as a risk factor for diverticulitis but is a risk factor for other gastrointestinal diseases.
Obesity: There is a strong connection between the development of diverticulitis and larger waists.
NSAIDs consumption
Smoking
Lack of physical activity

Pathophysiology of Diverticulitis

Diet, sedentary lifestyle, genetics, and certain medications’ use all lead to an altered microbiome in the colon. Diet also plays an important role in the development of bacterial stasis and fecalith, which further complicates the microbiota in the colon. All of this leads to altered microbial metabolism which affects the immune and hosts defense response. It also leads to impairment of mucosal barrier function allowing adherence of bacteria to the colonic wall. This causes the release of pro-inflammatory cytokines, resulting in inflammation.

What are the symptoms of diverticulitis?

Diverticulosis and Diverticulitis

Diverticulitis presents with sudden-onset, lower abdominal pain, and bloody stool. It may also present with nausea, vomiting, and fever. Depending on the colon affected, the pain may be felt on the left (sigmoid colon) or the right (ascending colon) side.

In complicated diverticulitis, the bacteria may spread to the abdominal lining, and cause peritonitis. Or the fecalith or inflammation may cause bowel obstruction. Extreme cases may result in the formation of the fistula with other organs in the abdominal cavity.

How is diverticulitis diagnosed?

Diverticulitis diagnosis is made using a contrast-enhanced CT scan. CT scan of the colon may show colonic wall inflammation and the presence of diverticula. It is important to note that colonoscopy and barium enema, modalities very commonly used for diagnosis of colonic pathologies, are strictly contraindicated in case of diverticulitis due to the high risk of diverticular perforation.

After diagnosis, diverticulitis is classified based on its severity into different stages:

Stage 0 – asymptomatic diverticulosis
Stage 1a – uncomplicated diverticulitis
Stage 1b – diverticulitis with phlegmonous peri diverticulitis
Stage 2a – diverticulitis with concealed perforation, and abscess with a diameter of one centimeter or less
Stage 2b – diverticulitis with abscess greater than one centimeter
Stage 3a – diverticulitis with symptoms but without complications
Stage 3b – relapsing diverticulitis without complications
Stage 3c – relapsing diverticulitis with complications
In the case of perforation, Hinchley classification is used to describe the said diverticular perforation:
● Hinchey I – localized abscess
● Hinchey II – pelvic abscess
● Hinchey III – purulent peritonitis
● Hinchey IV – feculent peritonitis

How is diverticulitis treated?

Treatment of diverticulitis depends on the case, as in is it complicated or uncomplicated diverticulitis. Uncomplicated diverticulitis is treated mainly with antibiotics, dietary changes, and pain management. Complicated diverticulitis, however, is treated with surgical interventions.

Antibiotic Therapy: Recommended antibiotics for diverticulitis are ciprofloxacin (Cipro), metronidazole (Flagyl), cephalexin (Keflex), and doxycycline (Vibramycin). Several guidelines recommend routine use of these for uncomplicated cases, however, there is not much supporting evidence. But if CT images show abscess formation, fistulas, or intestinal rupture, antibiotics are recommended routinely.

Dietary modifications: Dietary changes are recommended, and most patients are put on a low-fiber diet. However, there is no enough supporting evidence to prove that this can help treat diverticulitis.

Many researchers believe that a low-fiber diet just gives the colon an adequate time to heal, rather than help in the healing process. Some research even claims that a high fiber diet can help prevent diverticulitis. However, none of these claims can be supported with enough clinical evidence.

Pain Management: Acetaminophen and anti-spasmodic are recommended for pain treatment. NSAIDs are related to a high risk of complicated diverticulitis and must be avoided in patients with acute diverticulitis.

Along with all these, it is important to provide bowel rest. In general, a patient with uncomplicated diverticulitis will be put on a liquid diet for 2-3 days, along with a low-fiber diet to give the bowel enough time to heal.

Surgical Interventions: Surgery is the only choice of treatment for diverticulitis complicated by an abscess, fistula, or intestinal perforation. The general approach to such cases is resection with primary anastomosis (a connection between resected parts of the intestine).

What are the complications of Diverticulitis?

Diverticulitis can cause many painful and emergent complications like:

Peritonitis: Following rupture of a diverticulum, bacteria may escape and invade the abdominal lining causing peritonitis, a surgical emergency.
Abscess: Sometimes, the diverticula may get filled with pus, requiring surgical drainage and antibiotic treatment.
Fistula
Intestinal Obstruction
Adhesions
Strictures

Following any abdominal surgery, there is always a risk of adhesion and stricture formation. They are not exact complications of diverticulitis, but rather of the surgical treatment of diverticulitis.

My opinion

A healthy diet and an active lifestyle can go a long way for the prevention of colonic diseases like diverticular disease. It is important for individuals to pay attention to their health as not doing so has grave consequences. Also, appropriate use of antibiotics must be done, so as to prevent the development of antibiotic-resistant bacteria. Timely diagnosis is also crucial for diverticulitis.