Fecal Analysis

Question 1

How much stool the average adult excrete per day?

Answer 1

100-300 mg

Question 2

About how much of stool is water?

Answer 2

70%

Question 3

Of the remaining 30% of stool… what are the contents

Answer 3

• 50% is bacteria and cellular debris
• The remaining portion is…
• • Vegetable residues
• • Small amounts of fat
• • Epithelial cells from the GI tract

Question 4

About how much fluid enters into the GI tract before you have stool?

Answer 4

10 liters

Question 5

Evacuates feces reflect…

Answer 5

The space and size of the colonic lumen

Question 6

What is normal colonic transit time?

Answer 6

24-48 hours

Question 7

Small/dark/hard

Answer 7

Constipation

Question 8

Voluminous/odorous/floating

Answer 8

Malabsorbed fats or proteins

Question 9

Loose with mucus

Answer 9

IBS

Question 10

Loose with mucus and blood

Answer 10

• Inflammed bowel syndrome
• Shingella
• Carcinoma

Question 11

Skicky/black/tarry

Answer 11

Upper GI tract hemorrhage

Question 12

Voluminous/watery/little formed material

Answer 12

Non-invasive infection

Question 13

Pasty/gray/white/little odor

Answer 13

Bile duct obstruction

Question 14

T/F- Infants and elderly patients with diarrhea can be dangerous and fatal

Answer 14

True

Question 15

Diarrhea alternating with constipation is characteristic of…

Answer 15

irritable bowel syndrome

Question 16

How can you check stool for organisms or protoazoa?

Answer 16

Culture it

Question 17

How can you find viral agents?

Answer 17

Immune electron microscopy

Question 18

How do you check lactose intolerance?

Answer 18

• By administering pure lactose
• If adequate lactose is present, blood glucose levels should rise in about 60 minutes
• A lactose deficient patient will fail to achieve increased blood glucose levels
• And they will usually have cramping and diarrhea

Question 19

What occurs in people whose intestinal flora has been killed or disturbed by antibiotics?

Answer 19

C. Diff

Question 20

How do tests that look for blood in the stool work?

Answer 20

-Use the peroxidase activity of heme derivatives in oxidizing organic compounds

Question 21

What is the hemoglobin metabolite with peroxidase activity

Answer 21

Hematin

Question 22

What are also peroxidase enzymes?

Answer 22

Certain plant enzymes and materials derived from myoglobin

Question 23

This is black tarry stool that is secondary to large quantities of blood in the upper GI tract

Answer 23

Melena

Question 24

This is small amounts of blood that do not change the appearance of the stool

Answer 24

Occult blood

Question 25

This is the most widely used indicator to detect occult blood

Answer 25

Gum Guiac

Question 26

Does overt bleeding or obvious melena require detailed testing?

Answer 26

Nope- but it is important to determine if the red or black pigmentation is actually from blood (like pepto)

Question 27

When can bright red blood be seen on the stool?

Answer 27

- Hemorroidal bleeding - Ulcerative colitis - Friable adenomas - Superficially eroded carcinomas

Question 28

How long can melena persist without fresh blood

Answer 28

5 days

Question 29

How long will a test for occult blood remain positive

Answer 29

Several weeks

Question 30

What is the hope in screening for occult blood

Answer 30

To detect significant lesions when the are asymptomatic or localized so that treatment can be successful

Question 31

Causes of upper GI occult blood

Answer 31

- Peptic ulcer - Erosive gastritis - Gastric carcinoma

Question 32

Causes of Lower GI occult blood

Answer 32

- Carcinoma - Adenomatous Polyps - Diverticulitis

Question 33

How are patients usually screened for poop probs?

Answer 33

- Sent home with slides for multiple samples for multiple days - Avoid meat or aspirin for 1 week prior to testing

Question 34

How high can false negative results be?

Answer 34

As high as 20% (in patients with colon cancer or large adenomas)

Question 35

Why do false negatives occur

Answer 35

- Bleeding may be intermittent | - Too much time may elapse before applying the sample and performing the test

Question 36

When/how are microscopic exams performed?

Answer 36

- For detecting parasites and their ova - The stool must be fresh - To identify to the amoeba or other motile parasites, the stool must be warm

Question 37

What if you see visible striated meat fibers

Answer 37

Proteolysis is inadequate

Question 38

Should WBC be in the poop

Answer 38

Nope

Question 39

What does WBC in the poop indicate

Answer 39

Inflammation

Question 40

If unaltered RBC are present, what does this mean

Answer 40

usually come from the anus or the rectum | blood from higher in the GI tract would have damage to the cells

Question 41

If you have malabsortion problems, how does this show up?

Answer 41

-Excessive fecal fat excretion

Question 42

Lipase deficiency increases/decreases the proportion of neural fat?

Answer 42

Increases

Question 43

Patients with severe malabsorption problems have low/high albumin

Answer 43

Low

Question 44

Low albumin causes...

Answer 44

- Malnutrition - Excessive fecal loss - Edema