Lecture 3 - IBS Flashcards
Idiopathic syndrome characterized by
chronic abd pn
altered bowel habits
IN THE ABSENCE OF ANY ORGANIC CAUSE
IBS
Functional bowel disorder
Extraintestinal manifestations common
No biologic markers or confirmatory test (diagnosis via symptom-based criteria)
IBS
Proposed mechanisms for IBS?
Abnormal motility
Visceral hypersensitivity
intestinal inflammation
enteric infection (~10% diagnosed after episode of bacterial gastroenteritis)
Psychosocial abnormalities (psychosomatic)
[multifactorial in nature]
Describe the abd pn associated w/ IBS?
Crampy and intermittent
Usually in the lower quadrants
RELIEVED W/ DEFECATION
feeling of bloating (w/ or w/o actual distension)
Check out the bristol stool chart
Maybe throw a card in here?
IBS-C is constipation predominat. Patients typically report what?
Less than 3 BMs/week, with straing
IBS-D is diarrhea predominant, with pts reporting what?
More than 3 BMs/day, with urgency or fecal incontinence
Often, somatic or psychological complaints accompany IBS, such as?
dyspepsia, heartburn, chest pn, HAs, fatigue, myalgias, gynecologic ssx (impaired sexual fx, dysmenorrhea, dyspareunia), urologic ssx (increased frequency/urgency), anxiety, depression
Alarm ssx or sxx that are not compatible w/ IBS and require further evaluation for other causes include:
Rectal bleeding
Nocturnal/progressive abdominal pn
wt loss
laboratory abnormalities such as anemia, elevated inflammatory markers, electrolyte disturbances
Note that a diagnosis for IBS should exclude organic etiologies
Also remember this is a chronic condition, therefore an acute onset of ssx should raise suspicions for etiology other than IBS
In diagnosing IBS, pt hx is critical. Consider questiosn such as?
fam hx of GI neoplasm
IBD
Hyper/hypothyroidism
Malabsorption syndromes
psychiatric disorders
Medication/diet/exercise changes
Recent travel/illness
IBS diagnostic criteria includes more than 3 months of abd pain/discomfort AND altered bowel habits AND two/three of the following:
Relief w/ defecation
Onset associated w/ change in defecation frequency
Onset associated w/ change in stool appearance
What are some supporting criteria for IBS?
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
PE in IBS?
Unremarkable
W/w/o mild abdominal TTP (exaggerated if psychosomatic component is present)
Diagnostic testing for IBS includes routine screening labs (CBC, CMP, UA).
- IBS-D, screen for?
- IBS-C, asses with?
- Celiac Dz
2. plain abd films
Treatmetn strategies for IBS?
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)
IBS diet should include regularity and large meal avoidance. Also reduced intake of?
fat, insoluble fiber, caffeine, beans, cabbage, onions (and other gas producing foods – low FODMAPS)
Dietary mod for IBS-D?
Trial of lactose elimination
Trial of gluten elimination
Dietary mod for IBS-C?
Increase fiber in patients w/ IBS-C (low dose, titrate to effect)
Increase fluid intake
Non-diet, non-pharm tx considerations for IBS?
Increased physical activity
Psychological therapies (CBT, hypnotherapy, relaxation techniques)
Adjuntive pharmacologic therapy for IBS includes?
FIRST TRY DIETARY/LIFESTYLE MODS…. then…
Antispasmodics
Anti-constipation
Anti-diarrheals (SSRA, anbx)
Psychotropic agents
For pain/bloating of IBS, try antispasmodics, such as?
Dicyclomine
Hyosycamine
For the constipation of IBS-C, try?
FIRST, osmotic laxatives
Then,
Lubiprostone (for women > 18)
Linaclotide
For IBS-D, try antidiarrheals such as?
FIRST = loperamide
Then,
Bile salt sequestrants (if loperamide doesn’t work)
SSRAs
What are the stipulations for use of SSRAs in IBS-D?
Alosetron (SSRA) is reserved for diarrhea related to IBS-D who have failed to respond to other therapies (FEMALE PTs ONLY)
Ondanestron = off label
What’s a non-absorbable abx that’s useful in IBS-D w/o significant bloating?
rifaximin
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?
Amitriptyline
Nortriptyline
Desipramine
Imipramine
Regarding psychotropic agents, what’s a noteworthy caveat regarding their usage?
They are NOT used for their psychotropic effects… true psychiatric disorders should be addressed separately
Probiotics for IBS?
No proven clinical value but may have psychological effect on symptoms… Placebo…
Well-tolerated/cheap… worth a shot
