The commonest presenting symptom of diverticulitis is pain. Pain is usually left sided in the left lower quadrant region because this is the most common site for diverticula formation. Fever and other signs of systemic infection may be present if the disease progresses and leads to formation of localized abscess.

Other symptoms are:

• Nausea
• Vomiting
• Change in bowel habit
• Constipation
• Increased flatulence
• Diarrhea
• Bloated feeling [5]
• Bleeding 

The disease could mimic various types of gastrointestinal conditions because of the ability of diverticulosis to occur anywhere along the tract. On physical examination, there is:

• Localized abdominal tenderness in affected area
• If there is an abscess, a tender mass may be felt

Laboratory tests

They are used when the history and physical examination are inconclusive. They include:

• Complete blood count will show increased white blood cell count and reduced hemoglobin if bleeding is present.
• Blood chemistry to examine the levels of electrolytes in patients who have been vomiting.
• Renal function [6]
• Test for liver function and liver enzymes 
• Blood culture should be obtained before instituting antibiotics
• Pregnancy test  to rule out other conditions like extra-uterine pregnancy in a woman of childbearing age
• Urinalysis
• Urine culture

Imaging

• CT scan, when necessary, this is the imaging study of choice. Findings include inflammatory masses and bowel wall thickening.
• Contrast studies: Barium us contraindicated as there may be perforations and leakage of contrast into the peritoneal cavity could be disastrous. A water soluble contrast medium is preferred when a CT scan can’t adequately differentiate colon cancer from diverticulitis.
• Plain radiographs have no use in diagnosing this condition but may demonstrate associated obstruction and bowel perforation [7].
• Colonoscopy can be used after an acute episode to check the extent of the diverticulosis.

In patients with the acute uncomplicated type, conservative management achieves full remission in over 70% of cases. Some studies have shown that antibiotics worsen the inflammatory process. Conservative management includes:

• Clear liquid diet
• Resting the bowel
• IV fluids
• Managing the pain

Antibiotics, if used, are broad spectrum to cover aerobic and non-aerobic organisms. This could be a single or multi drug regimen. If diverticulitis is severe, as characterized by peritonitis and systemic signs of infection, hospitalization is required [8].

Surgery is indicated when there is a complication. Complications may include intestinal obstruction, presence of fistula, abscesses and peritonitis. At discharge, patient’s diet should be low in fat and high in fiber.

The following factors may worsen the prognosis:

• Coexisting medical problems
• The presence of complications
• Severity of the illness [4]

The cause if diverticula formation is yet unclear. There is however strong association with obesity, low fiber diet and constipation. When these pouches are present, there are now factors that could lead to inflammation and hence diverticulitis. Although the exact pathway by which diverticulitis occurs is unclear, there have been some postulations [2]:

• Collection of undigested food particles in the diverticulum
• Collection of fecal matter in the diverticulum
• Raised intraluminal pressure 
• Thickened food particles

Diverticulitis is mainly a disease of the elderly although it is now seen in younger age groups as well. The incidence increases with advancing age and 65% of people older than 85 years have diverticulitis. There is no sexual preference as the disease affects both sexes equally.

It is more common in industrialized countries compared to underdeveloped countries. This could be due to lifestyle and diet. It is seen more Caucasians and Asians than in blacks.

There are two ways by which diverticulosis is thought to occur. The first is erosion of the wall of the diverticula which leads to inflammation, necrosis and then perforation.
The second mechanism, which is also touted to be the commonest is obstruction of the diverticulum lumen. This obstruction is usually by undigested food particles or fecal matter. The obstruction then leads to distension due to mucus secretion within the diverticulum. Subsequently, the blood supply is compromised and this will cause perforations, both micro and macro, of the diverticulum[3].

Chronic diverticulitis could lead to fistula formation. Frequent bouts of diverticulitis can also cause intestinal obstruction when it causes scar formation which obstructs the colonic lumen.

In patients with risk for diverticulosis, and in those with asymptomatic types, the standard of prevention is a high-fiber diet [9].

In some people, there is some herniation of mucosa into the wall of the colon. This creates small pouches which are known as diverticula and the condition is known as diverticulosis. When one or more of this pouches get inflamed, it is called diverticulitis. Diverticulitis could be acute or chronic and it includes a wide range of conditions from asymptomatic forms to symptomatic forms [1].

Definition

Diverticulitis is a condition that results from inflammation of diverticula in the intestines. Diverticula are abnormal pouches that form on the walls of the intestines.

Cause

There is no clear cause. However, patients who have a high fiber diet, those who are obese, frequently constipated ones and older people tend to develop these pouches. When this pouches are present, they can be blocked by food or fecal particle which could lead to the processes causing diverticulitis.

Signs and symptoms

The commonest symptom of this disease is abdominal pain. It is usually on the left, like appendicitis but on the other side. Other symptoms include nausea, vomiting, diarrhea, increased flatulence, and constipation amongst others.

Diagnosis

Diagnosis is mainly by history and the examination by the doctor. Some laboratory tests like blood and urine tests may be done to check severity of the disease and the function of some organs in the body. Some imaging tests may also be carried out [10].

Treatment

For the mild type, treatment is conservative and patient may or may not require antibiotics. For the sever type, hospital stay would be necessary for close monitoring and patient may require surgery.

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