2. • Human feces are called stole
• It is the west residue of indigestible material
of an animal digestive tract expel through the
anus during defecation
• It have it’s own composition most of it is water
and there is bile pigment and salt
• Bacteria and inorganic material
3. Collection
• By following universals protocols
• Stole should be collection dry, sterilized wide
mouthed container
• It should be uncontaminated with urine or any
other body fluid
• Properly named and always fresh sample
should be tested
4. • There are two type of stole examination
namely the physical examination and the
microscopic examination
• In physical examination we look stole for
Colure
consistency
odor volume
Part of adult parasite
5. Stole examination
Method I: Physical examination
Purpose: Use of physical examination
• To expect intestinal disorders
• To give clue about cause of the disease
• To determine the consistency, color, and odor
of the stool sample
• To see some visible parasites e.g. Ascaris
6. Procedure:
1. The appropriate sample for physical examination
was collected after proper orientation given to the
patient
2. The color of the stool sample was seen under clean
stool cup
3. The consistency (formed, semi formed, watery, and
looseness) of the sample were observed
4. The results were recorded
7. Result: after careful observation
• Consistency- bulky, hard, loose, semisolid,
watery
• Color- black, bright red, mucous, white
• Presence of adult worms- hook worm, round
worm…
9. Color
• =>Black~ bleeding in the upper GIT, or iron
administration
• =>Bright red~ bleeding piles, lower level of GIT or
contamination with menstrual blood
• =>Mucous~ amoebic dysentery, jaundice or
obstruction to flow of bile to intestine
10. Source of error:
• Unclean sample container
• Contamination with urine
• Contamination with menstrual bleeding
• Delivered too long after collection (old
sample)
11. Method II: Wet mount preparation (direct saline)
Purpose: Use of direct wet mount
• To assess parasitic load
• To provide quick diagnosis
• To see organism motility (e.g, E.hisolytica,
G.lamblia, B.coli)
• To observe organisms not seen by permanent
stains
12. Principle: A drop of saline is added on clean
slide containing patients sample and seen
under low power objective to look for any
motile organism.
Material and reagent: PPE, normal saline
(0.85%), clean slide, cover slide, applicator
stick, stool cap, labeling material, Pasteur
pipette, waste container and microscope
13. Procedure:
1. A clean slide was labeled
2. A drop of saline was added on a clean slide
using Pasteur pipette
3. Using an applicator stick a sample of about
1gm (head of match stick) was transferred to the
slide containing saline to the slide
4. The saline and sample were mixed properly
14. 5. A cover slide was applied on that slide air
bubbles were not allowed to appear
6. The slide was then searched under low power
and 40× objective
15. Results: After looking under microscope
• Ova of Ascaris seen
• Trophozoite stage of Giardia seen
• Egg of T.trichuria seen
• Egg of S.mansoni seen
16. Clinical significance:
• Ascaris-Offensive pneumonia, lung tissue
damage
-Bowel obstruction
-Prevent host from digesting proteins
-Obstruction and inflammation of
appendix
18. • T.trichuria- Damage to intestinal mucosa
-Profuse mucus and bloody diarrhea
-Edematous prolapsed rectum
-Anemia due blood loss, weight loss,
malnutrition
19. Source of error:
• Oil immersion examination is not recommended
• Not seeing enough field and
• Too little or too much saline
• Unclean slide and cover slide
• Air bubbles while applying the cover slide
20. Method iii: Formalin concentration technique
Purpose: Preparing such solution used when
• Few number of parasites are present as
Schistosoma species
• To increase viability of parasites
21. • Principle: When stool sample is dissolved in
formalin ether as well as diethyl ether and
after centrifugation, high density sediments
including protozoan cyst and helminth eggs
goes lower to the bottom and low density
debris floats. A smear from the sediment is
made on slide seen for any parasites.
22. • Material and reagents: PPE, test tubes, formal
ether, beaker, rack, plastic pipette, applicator
stick, centrifuge, cover slide, slide, sieving
material, centrifuge, cover slide, labeling
material, gauze, and microscope, waste
container
23. Procedure: 1. 3ml of formalin was added to a test tube
• 2. A stool sample of about 1gm was added to that test tube
• 3. The test tube was then closed and the sample and formalin were
mixed by inverting the tube several times
• 4. 3ml of formalin was added again
• 5. The sample solution was then sieved on to beaker using gauze
• 6. 3ml of diethyl ether was poured to the filtered sample solution
• 7. The solution was then added to a test tube and centrifuged
• 8. After centrifugation the solution formed four layers (Ether,
debris, formalin, sediment) and the first three layers were discarded
• 9. The sediment was allowed to sat on a clean, labeled slides and
was seen under low power and 40× objective
24. Result: After looking under microscope
Ova of hookworm seen
Clinical significance:
Hookworm -A.duodenale and N.americanus
- Skin penetration result `ground itch`
-Larval migration to lung and trachea
-Intestinal blood loss and injury to
upper intestinal mucosa.
25. Source of error:
• Mislabeling of slides
• Incorrect measurement
• Incorrect centrifugation(time and centrifugal
force)
26. Method V: H.pylori antigen rapid test
• Purpose: To determine Whether a suspect has an
H.pylori infection
• Principle: an aliquot of diluted stool sample is
added to the sample well of the test cassette. The
sample flows through a label pad containing
H.pylori antibody coupled to red colored colloidal
gold. If the sample contains H.pylori antigens, the
antigen will bind to the antibody coated on the
colloidal gold particles to form antigen-antibody-
gold complex.
27. Material and reagent: PPE, stool sample, H.pylori antigen rapid
card, sample bottle, waste container
Procedure:
1. The material and specimen were brought to the working area
2. The cassette was removed from the sealed foil pouch
3. The sample bottle was made upright with the tip point toward the
direction away from the test performer, snap off the tip
4. The bottle was held in a vertical position over the sample well off
the cassette, 3 drops (120-150µl) of diluted stool sample were
delivered to the sample well
5. The result was recorded within 5-10 minutes. A strong positive
sample may show results earlier
28. Result: After prescribed time
• Positive; a distinct pink colored band appears
on the test line regions, control line regions
• Negative; no line appears in the test line
regions, a distinct pink line shows on the
control line region
• Invalid result; the control line next to the test
line does not become visible within prescribed
time after the addition of the sample
29. Clinical significance:
• H.pylori-accepted as the most common
cause of gastritis, gastric ulcer,
duodenal ulcer
-Gastric adenocarcinoma , primary
gastric B-cell lymphoma
-peptic ulcer, gastric cancer
30. Source of error:
• Expired kit
• Too long or too short time
• Improperly mixed sample
• Invalid test procedure
Note-if there is no line in the control region, the
procedure is said to be either invalid or false
positive and not accepted and the whole test
procedure should be repeated.
31. Method Iv: Kato Katz
Purpose: Used for
• Qualitative and semi-quantitative diagnosis of
intestinal helminthic infections
• To report number of parasites per gram of
stool
• To see parasites clearly as the glycerol on the
cellophane remove debris around the
parasites
32. • Principle: Fesces are pressed through a mesh
screen to remove large particles. After filling the
hole, the template is removed and the remaining
sample is covered with cellophane soaked in
glycerol, which clear the fecal material from
around eggs. Eggs are counted and reported as
number per gram of fasces.
• Material and reagents: PPE, clean slides, Kato set
(template, mesh paper, spatula), cellophane
soaked in glycerol, newspaper, stool sample,
applicator stick, microscope, waste container
33. • Procedure: 1. A clean slide was labeled
• 2. Using the applicator stick a stool sample was transferred to a
newspaper
• 3. Mesh screen was placed on the sample and using plastic spatula
it was scraped by pressing so that debris remains and most
probably well digested ruminants caught by spatula
• 4. The scratched fecal material on spatula was transferred to the
template hole (measures about 41.7mg) to fill the hole
• 5. The template was then carefully lifted off and after that a
cellophane was placed over fecal sample
• 6. Another slide was applied over the cellophane to spread sample
• 7. The second slide was carefully removed by gently sliding it
sideways
• 8. The number of parasites were counted, multiplied by 24 and
reported as parasite/gm
34. Result: after looking under microscope
Ova of S.mansoni seen
Clinical significance:
• S.mansoni- Skin penetration by cercaria,
swimmer`s itch
-Feeds circulating glucose and blood
product
-Fibrosis and scarring of affected tissues
-Egg travel to the liver
35. Source of error:
• Unlabeled slide
• Not seeing with specified time
• Error while removing second slide
• Too thick after applying cellophane
