Fecal Analysis

Question 1

Formation

Answer 1

9000mls fluid into small intest.
50-1500mls fluid into large intest.
- With foodstufs

18-24 hours for large intest. to eliminate waste (100-200g/day)

Question 2

Function of small intestine

Answer 2

Digestion and reabsorption

Question 3

Large intestine function

Answer 3

Reabsorption of water, Na, Cl

Question 4

Soft stool/diarrhea general causes

Answer 4

Excess fluid OR inadequate time in bowel

Question 5

Hard stool/constipation general causes

Answer 5

Increased water reabsorbed OR too long in the bowel

Question 6

Purpose of 72 hour stool sample

Answer 6

Daily excretion doesn’t correlate to what the patient ate in just the last 24 hours
- Quant. fecal fat
- Gas build up from bacteria

Question 7

Stuff that makes up brown color

Answer 7

Urobilin, bile pigments

Question 8

Pale colored stools are called what? What does this color indicate

Answer 8

Acholic
- decreased bile duct obstruction, barium sulfate enema

Question 9

Bright red stool means what

Answer 9

Fresh bleed, lower GI

Question 10

Black stool… what?

Answer 10

Old bleed, from upper GI, charcoal, iron

Question 11

Forms of stool and their meanings

Answer 11

Flat, ribbon like: obstruction
Bulky/floating: steatorrhea

Mucus
- Small amnts: straining, infections, dysentary
- Large amnts: villoous adenoma

Question 12

Significance of leukocytes

Answer 12

Abnormal, should be no PMNs
- Ulcertive colitis, dysentary, diverticulus, abscesses, eos in parasitic

Question 13

Fecal fat 2 slide purposes

Answer 13

Slide 1: neutral fats (nondigested)
- Normal <60 fat globs/HPF

Slide 2: soaps, fatty acids (digested)
- Normal <100 large fat globs/HPF

Question 14

Fecal fat slide mal- review

Answer 14

Maldigestion: slide 1 increased
Malabsorption: slide 2 ONLY increased

Question 15

Undigested muscle fiber

Answer 15

Striated in multiple directions
10 = significant for pancreatic insufficiency, biliary obstructions, fistulas

Question 16

Fecal occult blood guaiac indicator

Answer 16

Feces placed on guaiac card, H2O2 added and boom, blue color if there is hemoglobin

Question 17

iFOB immunoassay

Answer 17

More specific for human hemoglobin, like a pregancy test lateral flow

Question 18

First sign of colorectal cancer?

Answer 18

Fecal blood

Question 19

What is a melena

Answer 19

50-100mls/day of blood

Question 20

Quantitative fecal fat

Answer 20

72 hours
- set 100 g fat diet

Question 21

Steatorrhea numbers

Answer 21

Normal fecal fat: <6g/day
Abnormal fecal fat: >6g/day

Question 22

Maldigestion vs malabsorption

Answer 22

Maldigestion
- Cause: no fat breakdown
- Disease: live decreased bile, pancreatic decreased enzymes
- Qualitative fecal fat: slide 1 or both increased
- Quantitative fecal fat: not needed

Malabsorption
- Cause: no absorption of digested dfat
- Disease: congenital, inflammatory disease
- Qualitative fecal fat: only slide 2
- Quantitative fecal fat: >6g/day, <95% absorbed

Question 23

Secretory diarrhea findings

Answer 23

Mechanism: increased water secretions
Correlations: infections, drugs, gi inflamm
Lab: fecal wbcs, stool culture

Question 24

Osmotic diarrhea findings

Answer 24

Mechanism: increased water retention in gi
Correlations: maldigestion, malabsorption, intolerances
Lab: fecal osmotic gap, fecal carbs, electrolytes, fats

Question 25

Motility diarrhea findings

Answer 25

Mechanism: decreased time in bowel, super fast
Correlations: IBS, nerve conditions, early dumping syndrome