Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Gastro > Diarrhea, Lymphocytic colitis > Flashcards

Diarrhea, Lymphocytic colitis Flashcards

1
Q

Clinical definition of diarrhea?

A

Incr in frequency, volume, or urgency of defecation

+/- change in consistency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Nml stool frequency?

A

3 BM per week up to 3 BM per day

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Physiologic definition of diarrhea?

A

> 200 gm stool output per day

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Normal amount (liters) of input into the gut?

A

8.5L

2L from ingestion, 6.5L from secretions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The small intestine absorbs __L of fluid, and the colon absorbs __L.

A

7L

1.4L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How much fluid is excreted form the gut?

A

0.1L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the basis of nml fluid absorption?

A

Na+ uptake

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Receptors in small intestinal villi?

A

Na+ / glucose co-transporter

Na+ / H+ exchanger (NHE)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Receptors in Large intestinal crypts?

A

epithelial Na+ channel (ENaC)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Pathophysiology of Diarrhea?

A
  1. Increased intraluminal fluid

2. More rapid transit through GIT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Increased Intraluminal Fluid: Pathophysiologic Mechanisms?

A
  1. decr absorption (osmotic mechanism, fluid drawn into gut)
  2. incr secretion (active secretion of electrolytes + fluid into lumen)
  3. inflammation (inflammatory mediators stimulate secretion)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

comprise most stool osmolality

A

electrolytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What causes compromise of epithelial barriers?

A

cell death, caused by inflammation

**results in incr intraluminal fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How does ingestion of unabsorbable solutes affect the GIT?

A

incr intraluminal fluid via osmotic mechanism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Causes of Osmotic Diarrhea:

A

Non-absorbable carbohydrates

Non-absorbable electrolytes (laxatives)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Types of Non-absorbable carbohydrates?

A

lactose (milk, yogurt, cheese, etc.)

sorbitol, mannitol (diet soda, gum, candy)

lactulose (Rx for hepatic encephalopathy)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Types of Non-absorbable electrolytes?

A

Mg2+ compounds (MOM, Maalox, Epsom salts)

Golytely (PEG)

Fleets phosphosoda prep

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

The key to all secretory diarrheas is:

A

excessive Cl- secretion into the gut

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

oral rehydration formula for the treatment of cholera and other secretory diarrheas is based on:

A

exploitation of the Na/glucose co-transporter

By including glu in high salt drink, Na+ absorption can continue despite cAMP inhibition of Na+ absorption by NHE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Secretory Diarrhea Mediators:

Bacterial Enterotoxins?

A

Cholera toxin (cAMP)
E. coli LT (cAMP)
E. coli STa (cGMP)
Yersinia toxin (Ca2+)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Secretory Diarrhea Mediators:

Neurohumoral agents?

A

VIP (cAMP)
ACh (Ca2+)
Serotonin (Ca2+)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Secretory Diarrhea Mediators:

Immune mediators?

A

Histamine (cAMP)

Prostaglandins (cAMP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Chemical irritants that cause secretory diarrhea?

A

Bile, arsenic, caffeine, ETOH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Neuroendocrine tumors that cause secretory diarrhea?

A

VIPoma
carcinoid
medullary carcinoma of thyroid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
How does fasting affect osmotic diarrhea? How does fasting affect secretory diarrhea?
O: resolves with fasting S: persists with fasting
26
Which form of diarrhea is associated with flatulence?
osmotic
27
pH of stool in osmotic diarrhea? pH of stool in secretory diarrhea?
O: <5.3 S: 6-7
28
osmolar gap in osmotic diarrhea? osmolar gap in secretory diarrhea?
O: >125 S: <50 **=230-2(Na+K)
29
Pathophysiology of Inflammatory Diarrhea: | Stimuli?
``` Parasites Food allergy Celiac sprue Salmonella Whipples IBD GVH Shigella Rotavirus ```
30
Pathophysiology of Inflammatory Diarrhea: | Immune-mediated mechanisms causing enterocyte cell death?
complement, cytokines, cytotoxic T-cells, mast cells, neutrophils, etc.
31
inflammatory mediators induce...
Intestinal Secretion
32
what stimuli directly induce enterocyte death?
``` Amoeba Shigella Rotavirus Giardia Cryptosporidium ```
33
What are the consequences of inflmm diarrhea?
Villous atrophy | Malabsorption
34
Acute Diarrhea: Duration? Etiology? Prognosis?
<3 weeks infectious self-limited
35
Acute Diarrhea: Pathophys? Management?
secretory or inflammatory supportive
36
Most Common Causes of Infectious Diarrhea in the US?
``` Viral E. coli Campylobacter Salmonella, Shigella Giardia Cryptosporidium (AIDS) C. difficile (antibiotics) ```
37
Most Common Causes of Infectious Diarrhea in the 3rd world?
``` Viral (rotavirus, norovirus) Campylobacter E. coli Vibrio cholerae Entameba histolytica Salmonella, Shigella Cryptosporidium (infants) ```
38
Most common cause of traveler's diarrhea?
enterotoxigenic E coli
39
Who is affected by traveler's diarrhea?
travelers to third world
40
Prophylaxis Recommendations for traveler's diarrhea?
eat only cooked foods drink only bottled beverages, avoid ice wash hands before meals consider peptobismol QID
41
Trx for traveler's diarrhea?
po fluids + anti-diarrheals for symptom control if severe, ciprofloxacin 500 mg BID x 3 days
42
What type of acute diarrhea is likely viral or toxin mediated?
Non-bloody diarrhea without dehydration
43
What type of acute diarrhea is likely bacterial?
bloody (dysentery) diarrhea without dehydration
44
Treatment of diarrhea without dehydration?
fluids and peptobismol
45
Treatment for bloody diarrhea with dehydration?
IV fluoroquinolone (cipro) hospitalization IV fluids
46
C. diff risk factors?
Antibiotic usage Extremes of age Hospitalization or institutionalization
47
How does C. diff induce diarrhea?
Cytotoxins A & B
48
How is C diff diagnosed?
pseudomembraneous colitis on endoscopy Stool assay for Toxin A (+/- B)
49
How is C diff treated?
stop the offending abx (if possible) metronidazole or vancomycin po cholestyramine to bind toxins
50
Chronic diarrhea: Duration? Etiology?
>3 weeks infectious immune-mediated malabsorption
51
Chronic diarrhea: | Pathophys?
osmotic, secretory (no mucosal injury) Inflammatory (mucosal injury)
52
What types of chronic diarrheas are associated with NO mucosal injury?
1. maldigestion/malabsorption syndromes 2. hypermotility (thyroid, IBS, etc) 3. Neuroendocrine malignancies 4. factitious (laxative abuse)
53
Clinical features of lactase deficiency?
1. osmotic diarrhea 2. flatulence 3. acidic stool pH
54
Clinical features of bacterial overgrowth?
secretory diarrhea (due to conversion to unconjugated bile acids) osmotic diarrhea gas
55
IBS is a disorder of
motility and pain perception
56
Symptoms of IBS?
1. abdominal pain 2. bloating 3. no weight loss, bleeding, malnutrition, anemia
57
Treatment of: IBS w/ diarrhea? IBS w/ const?
anti-cholinergic medications (diarrhea) 5-HT receptor antagonists (constipation)
58
What types of chronic diarrheas are associated with mucosal injury?
1. chronic infections (HIV, parasites, sprue) 2. allergic/immune-mediated (celiac, Crohn's, ulc colitis, etc) 3. malignancies (colon CA, lymphoma)
59
What are the 2 types of microscopic colitis? What are the associated symptoms?
Collagenous colitis Lymphocytic colitis Chronic watery, non-bloody diarrhea in adults
60
Treatment for microscopic colitis?
Bismuth Aminosalisylates steroids
61
What are the features of Behcet's disease?
1. generalized vasculitis 2. Oral and genital aphthous ulcers 3. Uveitis 4. GI tract ulcers 5. Non-erosive arthritis
62
Trx of Behcet's?
immunosuppressants
63
What are "red flags" in a patient with chronic diarrhea?
1. Unintentional weight loss 2. Nocturnal diarrhea 3. Signs of malnutrition (muscle wasting) 4. Rectal bleeding
64
What is the ddx of there are no red flags + flatulence?
lactose intol | bac overgrowth
65
What is the ddx of there are no red flags + pain with BMs?
IBS
66
What is the ddx if Red Flags Present or Initial Studies Abnormal + weight loss?
IBD hyperthyroidism malabs malignancy
67
What is the ddx if Red Flags Present or Initial Studies Abnormal + bleeding?
malignancy infection IBD

Gastro (25 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions