Fobt Flashcards
Components of a Normal Stool
• Bacteria
• Undigested food stuff
• Bile pigments (Urobilin/ Stercobilin)
• Water and electrolytes
• Enzymes
Solid/ semi-solid body waste discharged from the large
intestine through
the anus
during defecation.
Feces/stool
Enzymes in stool
a. Trypsin
b. Chymotrypsin
c. Aminopeptidase d. Lipase
e. Amylase
Volume per day
100-200 g/day
Color of stool
Light to dark brown
Odor of stool
Offensive
Why is it offensive due to
Indole and skatole
Form and consistency of stool
Soft and well formed
Reaction alkaline
Increase protein diet
reaction acidic
Increase vegetable, CHO, and fats in the diet
Abnormal color of stool
Black
Red
Green
Pale yellow
White
Gray
When stool if black
upper gastrointestinal bleeding, intake iron, etc.
When stool is red
bleeding in lower GIT, intake of beets, food
coloring, Rifampin and Pyridium compounds
When stool is gray white pale yellow
Bile duct obstruction, Barium intake
When stool is green
Presence of biliverdin, Oral antibiotics, Green Vegetables
Abnormal Variation in Consistency
Soft and watery
Hard and scybalous (like gout dropping)
Bulky frothy stool
Ribbon like stool
Mucus and blood streak
Rice watery stool
When soft and watery
Diarrhea
When hard and scybalous
Spastic constipation
When bulky frothy
Bile duct obstruction, Pancreatic disorders, abundant fats
When has Mucus and blood streak
Amoebic colitis, Dysentery, Malignancy
When rice watery stool
Cholera
Western stool chart
Bristol stool chart
Type: Separate hard lumps, like nuts (hard to pass)
Type 1
Type: Sausage-shaped but lumpy
Type 2
Type: Like a sausage but with cracks on its surface
Type 3
Type: Like a sausage or snake, smooth and soft
Type 4
Type: Soft blobs with clear-cut edges (passed easily)
Type 5
Type: Watery, no solid pieces. Entirely Liquid
Type 7
Random samples used for
cultures
ova and parasites (O&P)
microscopic examination for cells
fats and fibers
detection of blood
Characteristics of fecal container
cardboard containers with wax-coated interiors or plastic containers with wide openings and screwcapped tops
Type: Fluffy pieces with ragged edges, a mushy stool
Type 6
The stool collected should only be about
Thumb size
Pea size
Soft specimen
5-6spoonful off watery specimen
Patients should understand that the specimen must not be contaminated with
urine, toilet water, fibers, gauze threads, and tissue papers.
Preservation of Stool
•Refrigeration
•Chemical Preservative
Chemical Preservative used
- Sodium Acetate
- Formalin
-Merthiolate Iodine Formaldehyde -NSS w/ glycerine
-Polyvinyl Acohol
Different Types of Indicator Chromogens
•Gum Guaiac •Benzidine •Ortho toluidine
Dietary Restrictions 3 days before the examination (FOBT)
• Red Meat
• Horse radish • Melons
• Raw broccoli • Cauliflower •Turnip
• Vitamin C
Hidden Blood not seen by microscopic examination
Fecal Occult Blood Testing (FOBT)
FOBT Normally found in small amount,
2.5ml/150g of stoool
FOBT IS SCREENIBG TEST FOR
Screening test for colorectal cancer and GIT
Principle of FOBT
- Based on the pseudoperoxidase activity of hemoglobin molecule reacting with chromogen.
is the trace amount of blood in feces which cannot be seen with eyes.
FOBT
The test cassette/strip should be used within _________ after taking out from the foil envelope.
1 hour
Squeeze _____ drops (about 80 uL) of sample solution to the sample well, as in the illustration.
3 drops
Read the test results after_____ minutes.
10 mins
Positive result
If control and test line are rose pink
Do not read results after _____ mins
15mins
It could be the early clinical symptom of the common
Malignant tumor
Gastric cancer
Colonic cancer
Ulcer
The test devices should be stored at
4-30C
Specificity of test
99.40%
Sensitivity of test
96.88%
Total agreement test
99.00%
