Diverticular Disease

Diverticular disease (diverticulosis) is the presence of localized outpouchings in the bowel wall. It can be caused when a chronic lack of dietary fiber occurs, but there are also some genetic consequences. This explains why the diverticular disease is very rare in underdeveloped countries.

Diverticular disease usually affects the sigmoid colon.

Pathophysiology and pathology
In diverticular disease, the bowel wall is thicker due to much more elastic tissue between the muscle fibers. High intraluminal pressure due to high amplitude contractions combined with constipated stool and functional hypersegmentation results in evagination of the bowel wall and thus diverticulosis.

Clinical signs
Diverticular disease can be asymptomatic. When symptoms occur, the clinical signs include :
 * chronic diverticular pain
 * rectal bleeding
 * obstipation
 * small feces
 * episodic diarrhea

Diagnostics
Clinical signs will let doctor know about some process in the alimentary tract. Although colonoscopy is not recommended when an inflammation of diverticula is present, it is usually performed to see what is wrong in the large intestine. Diverticula are shown in the endoscopy image quiet well (see image).

If ultrasonography is performed, experienced doctor can see thickened bowel wall and changed structure of the intestinal loops.

Computed tomography (CT) can show thickened bowel wall as well and if perforations, abscesses or adhesions are present, they can be visible too.

Bleeding
Bleeding can occur in 20% of patients. Most of them are in a higher risk of bleeding because of hypertension, atherosclerosis or regular usage of non-steroidal anti-inflammatory drugs. However, these bleedings are usually self-limited and stop spontaneously. Diagnosis of diverticular bleeding can be made by colonoscopy or mesenteric angiography and in severe cases can be stopped by coiling or by emergency surgery.

Note: It is recommended to perform a surgery in patient with 6-units bleeding within 24 hours.

Inflammation
Diverticulitis is an inflammation of the diverticula. Clinical signs will include fever, anorexia, left lower quadrant abdominal pain and diarrhea. Some patients can end with peritonitis after perforation of an inflamed diverticulus and have to undergo an immediate laparotomy.

Computed tomography (CT) can show thickened bowel wall (more than 4 mm ) and inflammation within the pericolic fat or collection of fluid. Using the barium-based contrast material or colonoscopy is strictly prohibited as the risk of perforation is very high.

Therapy includes stopping oral intake, giving intravenous fluids and combination of intravenous antibiotics is used: ciprofloxacin and metronidazole or combitation of trimethoprim/sulfamethoxazole. This covers aerobic gram-negative rods and anaerobic bacteria. This does not affect entercocci, so ampicillin can be added in some cases.

Other complications
Other complications include :
 * pericolic abscess
 * intraperitoneal perforation
 * fistula formation into other abdominal or pelvic viscera
 * bowel-to-bowel adhesions
 * fibrous strictures of bowel

Treatment
Asymptomatic diverticular disease may be treated only by diet alterations. The food should contain enough fiber.

Symptomatic disease with inflammation should by managed by antibiotics and bowel rest.

Surgical therapy includes proximal diversion of the fecal stream with an ileostomy or a colostomy, resection of the bowel part with pouch and anastomosis or diversion.