Occult Blood Flashcards
1
Q
What is fecal occult blood?
A
Presence of hidden or unseen blood in the stool which can be detected by performing fecal occult blood test
2
Q
How does blood appear in upper vs lower GI tract?
A
- Upper: dark or mohagany
- Lower: bright red
3
Q
Can fecal occult blood be identified macroscopically?
A
Yes, when present in a large amount
4
Q
What is fecal occult used to detect?
A
Detecting and localizing diseases of the GI tract
5
Q
What is fecal blood an indicator of?
A
Colorectal cancer
6
Q
What percentage can early detection of colorectal cancer decrease mortality by?
A
15-35%
7
Q
How is the sample for fecal occult collected?
A
- Pt self-collection
- Pt instructed to eat meat free for 3 days prior to test
- Pt placed in high fiber diet (lettuce, corn, bran)
- Given 3 test cards to take home
8
Q
How does the Pt utilize the 3 test cards?
A
- 3 specimens from 3 separate days
- Use aliquot from the center of sample
- Avoid contamination of sample (urine, toilet water)
- Apply very thin smear to slide
- To test, apply two drops to back of slide
9
Q
What is a positive reaction to fecal occult?
A
Indicated by appearance of blue color
10
Q
What is a negative reaction to fecal occult?
A
No blue color reaction
