Diverticulitis is a common digestive disease which involves the formation of pouches (diverticula) within the bowel wall. This process is known as diverticulosis, and typically occurs within the large intestine, or colon, although it can occasionally occur in the small intestine as well. Diverticulitis results when one of these diverticula becomes inflamed.
People often have left lower quadrant abdominal pain and tenderness, fever, and an increased white blood cell count. They may also complain of nausea or diarrhea; others may be constipated. The severity of symptoms depends on the extent of the infection and complications. Less commonly, an individual with diverticulitis may have right-sided abdominal pain. This may be due to the less common right-sided diverticula or a highly redundant sigmoid colon. Some patients report bleeding from the rectum.
What causes Diverticulitis?
The causes of diverticulitis are poorly understood. About 40% of the risk of disease is believed to be due to genetics while 60% is due to environmental factors. Obesity is another risk factor.
Diagnosis of Diverticulitis
People with the above symptoms are commonly studied with computed tomography, or CT scan. The CT scan is very accurate (98%) in diagnosing diverticulitis. In order to extract the most information possible about the patient’s condition, thin section (5mm) transverse images are obtained through the entire abdomen and pelvis after the patient has been administered oral and intravascular contrast. Images reveal localized colon wall thickening, with inflammation extending into the fat surrounding the colon. The diagnosis of acute diverticulitis is made confidently when the involved segment contains diverticulae. CT may also identify patients with more complicated diverticulitis, such as those with an associated abscess. It may even allow for radiologically guided drainage of an associated abscess, sparing a patient from immediate surgical intervention.
Other studies, such as barium enema and colonoscopy are contraindicated in the acute phase of diverticulitis due to the risk of perforation.
Differential diagnosis – The differential diagnosis includes colon cancer, inflammatory bowel disease, ischemic colitis, and irritable bowel syndrome, as well as a number of urological and gynecological processes.
In complicated diverticulitis, bacteria may subsequently infect the outside of the colon if an inflamed diverticulum bursts open. If the infection spreads to the lining of the abdominal cavity, (peritoneum), this can cause a potentially fatal peritonitis. Sometimes inflamed diverticula can cause narrowing of the bowel, leading to an obstruction. Also, the affected part of the colon could adhere to the bladder or other organ in the pelvic cavity, causing a fistula, or abnormal connection between an organ and adjacent structure or organ, in this case the colon and an adjacent organ.