IBS & Diverticulosis

Question 0

What is the most commonly diagnosed GI condition?

Answer 0

IBS.

Question 1

What is IBS, irritable bowel syndrome?

Answer 1

Recurrent abdominal pain or discomfort associated with two or more of the following:

(1) improvement with defecation
(2) onset associated with change of frequency of stool
(3) onset associated with change of form of stool.

Question 2

What is the expected decrease is life expectancy when diagnosed with IBS?

Answer 2

No decrease.

Question 3

What are the 2 main types of IBS?

Answer 3

(1) IBS-C: slow colonic transit

(2) IBS-D: accelerated colonic transit

Question 4

What is visceral hypersensitivity?

Answer 4

Increased sensation in response to stimuli, perhaps due to an abnormal stimulus or abnormal central pain processing.

Question 5

Which IBS subtype is more likely to experience an increase in abdominal girth with bloating?

Answer 5

IBS-C.

Question 6

What is a possible cause of abdominal distention in IBS?

Answer 6

Gas retention due to impaired gas transit.

Question 7

What are studied associations of bacteria and IBS?

Answer 7

(1) There is an increased risk of IBS after a bacterial (or really any) infection
(2) Treatment of small intestinal bacterial overgrowth reduces IBS symptoms

Question 8

What are differences in gas production between the 2 subtypes of IBS?

Answer 8

IBS-D has higher hydrogen and negligible methane. IBS-C has both hydrogen and methane.

Question 9

What are FODMAPs?

Answer 9

Fermentable (by colonic bacteria) oligosaccharides, disaccharides, monosaccharides and polyols. They are associated with the induction of IBS symptoms.

Question 10

What is a possible way of determining which foods should be eliminated from the diet in order to improve IBS symptoms?

Answer 10

Remove those foods for which there are high IgG titers in the serum.

Question 11

Which other GI disorder has an association with IBS?

Answer 11

Celiac disease. Gluten-free diets can improve the symptoms of some IBS patients (more IBS-D than IBS-C).

Question 12

What type of immune cell is most notably increased in IBS?

Answer 12

Mast cells.

Question 13

What psychosocial factors are associated with IBS?

Answer 13

Increased abuse, stress, anxiety, depression are risk factors for IBS.

Question 14

What is diverticulosis?

Answer 14

Refers to the presence of diverticula, sac-like protrusions from the colonic wall.

Question 15

What is the distinction between a false and true diverticulum?

Answer 15

A true diverticulum contains all layers of the colonic wall. Most diverticula are false.

Question 16

Where are diverticula typically located?

Answer 16

The descending and sigmoid colon.

Question 17

What is the pathogenesis of diverticulosis?

Answer 17

Increased elastin deposition leads to thickened teniae coli, a high contractility, and thickened circular muscle. This leads to decreased luminal diameter and increased intraluminal pressure. At the same time, increased collagen and collagen cross-linking leads to increased rigidity, thus an impaired ability to accommodate the increase in pressure.

Question 18

What changes in neurotransmitter production influence diverticulosis?

Answer 18

Increases in serotonin and acetylcholine and decreases in NO and VIP lead to increased motility and intraluminal pressure.

Question 19

What profile is at increased risk of diverticulosis?

Answer 19

An obese, elderly individual with low physical activity and a low-fiber, high-fat, high-red meat diet.

Question 20

What is diverticulitis?

Answer 20

Inflamed diverticulosis.

Question 21

What is SCAD?

Answer 21

Segmental colitis associated with diverticulosis. It is a form of diverticulitis and may be a precursor to IBD.

Question 22

What is SUDD?

Answer 22

Symptomatic uncomplicated diverticular disease. Symptoms of diverticulosis without overt macroscopic colitis or diverticulitis.

Question 23

What is the pathogenesis of diverticulitis and its complications?

Answer 23

(1) Erosion of the colonic wall
(2) Inflammation
(3) Focal necrosis
(4) Perforation leading to obstruction, fistula, or peritonitis

Question 24

What is the pathogenesis of diverticular bleeding?

Answer 24

(1) As the diverticulum herniates, the vasa recta that supplies blood becomes exposed in the lumen
(2) Segmental weakness of the artery
(3) Rupture