Lecture 3 - IBS

Question 1

Idiopathic syndrome characterized by

chronic abd pn

altered bowel habits

IN THE ABSENCE OF ANY ORGANIC CAUSE

Answer 1

IBS

Question 2

Functional bowel disorder

Extraintestinal manifestations common

No biologic markers or confirmatory test (diagnosis via symptom-based criteria)

Answer 2

IBS

Question 3

Proposed mechanisms for IBS?

Answer 3

Abnormal motility

Visceral hypersensitivity

intestinal inflammation

enteric infection (~10% diagnosed after episode of bacterial gastroenteritis)

Psychosocial abnormalities (psychosomatic)

[multifactorial in nature]

Question 4

Describe the abd pn associated w/ IBS?

Answer 4

Crampy and intermittent

Usually in the lower quadrants

RELIEVED W/ DEFECATION

feeling of bloating (w/ or w/o actual distension)

Question 5

Check out the bristol stool chart

Answer 5

Maybe throw a card in here?

Question 6

IBS-C is constipation predominat. Patients typically report what?

Answer 6

Less than 3 BMs/week, with straing

Question 7

IBS-D is diarrhea predominant, with pts reporting what?

Answer 7

More than 3 BMs/day, with urgency or fecal incontinence

Question 8

Often, somatic or psychological complaints accompany IBS, such as?

Answer 8

dyspepsia, heartburn, chest pn, HAs, fatigue, myalgias, gynecologic ssx (impaired sexual fx, dysmenorrhea, dyspareunia), urologic ssx (increased frequency/urgency), anxiety, depression

Question 9

Alarm ssx or sxx that are not compatible w/ IBS and require further evaluation for other causes include:

Answer 9

Rectal bleeding

Nocturnal/progressive abdominal pn

wt loss

laboratory abnormalities such as anemia, elevated inflammatory markers, electrolyte disturbances

Question 10

Note that a diagnosis for IBS should exclude organic etiologies

Answer 10

Also remember this is a chronic condition, therefore an acute onset of ssx should raise suspicions for etiology other than IBS

Question 11

In diagnosing IBS, pt hx is critical. Consider questiosn such as?

Answer 11

fam hx of GI neoplasm

IBD

Hyper/hypothyroidism

Malabsorption syndromes

psychiatric disorders

Medication/diet/exercise changes

Recent travel/illness

Question 12

IBS diagnostic criteria includes more than 3 months of abd pain/discomfort AND altered bowel habits AND two/three of the following:

Answer 12

Relief w/ defecation

Onset associated w/ change in defecation frequency

Onset associated w/ change in stool appearance

Question 13

What are some supporting criteria for IBS?

Answer 13

Increase/decrease stool frequency

Abnormal stool form (lumpy, hard, loose, watery)

Abnormal stool passing (straining, urgency, feeling of incomplete passage)

Pasage of mucus

Abdominal bloating/distension

Question 14

PE in IBS?

Answer 14

Unremarkable

W/w/o mild abdominal TTP (exaggerated if psychosomatic component is present)

Question 15

Diagnostic testing for IBS includes routine screening labs (CBC, CMP, UA).

1. IBS-D, screen for?
2. IBS-C, asses with?

Answer 15

1. Celiac Dz

2. plain abd films

Question 16

Treatmetn strategies for IBS?

Answer 16

Pt reassurance and education (may express concern over definite/organic etiology)

Educate pts on chronicity of situation (ssx will wax/wane)

Psychosomatic vicious cycle (anxiety -> worse ssx)

Question 17

IBS diet should include regularity and large meal avoidance. Also reduced intake of?

Answer 17

fat, insoluble fiber, caffeine, beans, cabbage, onions (and other gas producing foods – low FODMAPS)

Question 18

Dietary mod for IBS-D?

Answer 18

Trial of lactose elimination

Trial of gluten elimination

Question 19

Dietary mod for IBS-C?

Answer 19

Increase fiber in patients w/ IBS-C (low dose, titrate to effect)

Increase fluid intake

Question 20

Non-diet, non-pharm tx considerations for IBS?

Answer 20

Increased physical activity

Psychological therapies (CBT, hypnotherapy, relaxation techniques)

Question 21

Adjuntive pharmacologic therapy for IBS includes?

Answer 21

FIRST TRY DIETARY/LIFESTYLE MODS…. then…

Antispasmodics
Anti-constipation
Anti-diarrheals (SSRA, anbx)
Psychotropic agents

Question 22

For pain/bloating of IBS, try antispasmodics, such as?

Answer 22

Dicyclomine

Hyosycamine

Question 23

For the constipation of IBS-C, try?

Answer 23

FIRST, osmotic laxatives

Then,

Lubiprostone (for women > 18)
Linaclotide

Question 24

For IBS-D, try antidiarrheals such as?

Answer 24

FIRST = loperamide

Then,

Bile salt sequestrants (if loperamide doesn’t work)
SSRAs

Question 25

What are the stipulations for use of SSRAs in IBS-D?

Answer 25

Alosetron (SSRA) is reserved for diarrhea related to IBS-D who have failed to respond to other therapies (FEMALE PTs ONLY)

Ondanestron = off label

Question 26

What’s a non-absorbable abx that’s useful in IBS-D w/o significant bloating?

Answer 26

rifaximin

Question 27

Psychotropic agents are most useful in patients w/ abd pn or bloating as main complaint. It’s also more useful in IBS-D due to anticholinergic effect. Some TCA options include?

Answer 27

Amitriptyline
Nortriptyline
Desipramine
Imipramine

Question 28

Regarding psychotropic agents, what’s a noteworthy caveat regarding their usage?

Answer 28

They are NOT used for their psychotropic effects… true psychiatric disorders should be addressed separately

Question 29

Probiotics for IBS?

Answer 29

No proven clinical value but may have psychological effect on symptoms… Placebo…

Well-tolerated/cheap… worth a shot