Case 4

Image: uncomplicated diverticula in the sigmoid colon

This is a picture of uncomplicated diverticula in the sigmoid colon, found incidentally at a post-mortem in a patient who died of unrelated causes.

Which of the following statements regarding colonic diverticula are true? (Tick all those that apply)

	a)	They are true diverticula which contain all the layers of the colonic wall.
	b)	The sigmoid and rectum are the commonest site, as faeces are most solid here and require higher pressure to propel.
	c)	Their presence stimulates hypertrophy of the circular muscle layer of the large bowel.
	d)	They tend to arise at weak point where blood vessels penetrate the submucosa of the large bowel.
Correct. Colonic diverticula are outpouchings of the mucosal layer of the large bowel through the submucosa and circular muscle layer of the bowel. Colonic diverticula are virtually restricted to the sigmoid colon only; the rectum is spared as its complete longitudinal muscle coat protects against their development. Diverticula stimulate marked hypertrophy of the circular muscle layer of the muscle coat. They tend to arise at weak points where blood vessels penetrate the submucosa. Incorrect. Colonic diverticula are outpouchings of the mucosal layer of the large bowel through the submucosa and circular muscle layer of the bowel. Colonic diverticula are virtually restricted to the sigmoid colon only; the rectum is spared as its complete longitudinal muscle coat protects against their development. Diverticula stimulate marked hypertrophy of the circular muscle layer of the muscle coat. They tend to arise at weak points where blood vessels penetrate the submucosa. Your answer has been saved.

Which of the following statements regarding complications of diverticula are true? (Tick all those that apply)

	a)	Acute diverticulitis is a common cause of right iliac fossa pain in elderly people.
	b)	A diverticular stricture may closely mimic a colonic adenocarcinoma.
	c)	Erosion of a large submucosal vessel may cause torrential per rectal bleeding.
	d)	Perforation of an inflamed diverticulum may cause generalized peritonitis.
Correct. Acute diverticulitis is a common cause of left iliac fossa pain in elderly people. A diverticular stricture may very closely mimic a colonic adenocarcinoma, both clinically and radiologically. Erosion into a large submucosal vessel may lead to marked per rectal bleeding. Perforation of an inflamed diverticulum is a common cause of generalized peritonitis. Page reference for both questions: 170-1 Incorrect. Acute diverticulitis is a common cause of left iliac fossa pain in elderly people. A diverticular stricture may very closely mimic a colonic adenocarcinoma, both clinically and radiologically. Erosion into a large submucosal vessel may lead to marked per rectal bleeding. Perforation of an inflamed diverticulum is a common cause of generalized peritonitis. Page reference for both questions: 170-1 Your answer has been saved.

Carton, Daly & Ramani: Clinical Pathology - Case Studies