(P) Lab 2: Direct Fecal Smear, Specimen Collection, and Processing Flashcards
Rupert-based
TOF. Ovum refers to the eggs stage of the parasites.
T (ova or ovum)
What to consider in macroscopic examination? (2)
color, gross abnormalities and consistency
Two components associated with routine parasitology?
- Macroscopic
- Microscopic
In microscopic examination, what is looked out for?
- Ova
- Parasite
- Fecal artifacts
TOF. The typical stool collection protocol consists of four (4) specimens.
F (3)
How many is the total specimen collected in 10 days?
3
In cases of amebiasis, how many specimens in 14 days is acceptable?
A. 3
B. 6
C. 9
D. 12
B
Stool samples from patients undergoing therapy that includes except:
A. Barium
B. Antacids
C. Bismuth or mineral oil
D. laxatives
E. NOTA
E
TOF
In specimen collection of a patient with antimalarial medications, they are delayed for a month following therapy
F (2 weeks)
The acceptable amount of stool required for PARASITE study
2-5g
TOF. Urine with poop is allowed as it is part of the human body and considered to be typical.
F (not allowed as it may destroy some parasites due to its acidity)
TOF. In case of no wide-mouthed containers, the poop may be put in a tissue.
F (tissue mask parasites or make examination of the sample difficult)
TOF. Temporary storage of fecal samples in a refrigerator (3 to 5 C) is acceptable.
T
The recommended time frame for liquid stool
within 30 minutes of passage.
Semi-formed stool should be examined within?
1hr
This type of stool specimens can be held for 24 hours following collection.
Formed-stool
Whch information of a specimen container does not belong:
A. Travel history
B. Physician’s name
C. Medical Technologist’s name
D. Clinical findings
E. NOTA
C
How many stool samples should be collected when following the
typical O&P collection protocol?
3
ratio of fixative to stool specimens
3:1
Before processing, what is done to the specimen?
specimen must be fixed in the preservative for at least 30
minutes before processing begins.
Which of these procedures is involved in the microscopic examination of stool
specimens for parasites?
A. Performing a concentration technique
B. Determining specimen consistency
C. Examining sample for gross abnormalities
D. Analyzing sample for color
A
used to measure objects observed microscopically accurately.
Ocular
Micrometer
disk inserted into the eyepiece of the microscope
diagnostic stages of parasites detected microscopically are measured in units
known as?
microns
Direct Wet Preparation
Slide may by mixing a small portion (2g) of unfixed
stool with?
saline or iodine
Direct Wet Preparation
reagent of choice
.85 saline soln
Direct Wet Preparation
suggested size for the glass slide
3 x 2
22mm square cover slip is utilized
Direct Wet Preparation
Trophozoites can be stained to demonstrate the nuclear morphology using?
Nair’s buffered
methylene blue solution (BMB)
Direct Wet Preparation:
Nair’s buffered
methylene blue solution (BMB): pale blue indicates?
Entamoeba cytoplasm
is stained
Direct Wet Preparation
Nair’s buffered
methylene blue solution (BMB): darker blue indicates?
nucleus
is stained
What prep is made to enhance the detail of the protozoan cysts
Direct wet iodine preparation
Direct wet iodine preparation
TOF. It destroys the TROPHOZOITES stage of
protozoan
T
Direct wet iodine preparation
cytoplasm will color
Yellow
Direct wet iodine preparation
nucleus will color
pale and refractile
Direct wet iodine preparation
glycogen
deep brown
structures that closely resemble parasites but in
reality, are not.
Artifacts and Confusers
TOF. Artifacts and Confusers’ presence of free-living organisms in stool caused by
specimen contact with water, sewage, or soil may often cause confusion
T
Artifacts and confusers
Which does not belong:
A. Stain precipitate
B. RBC abnormalities
C. Clumping plateles
D. WBC
E. Howell-Jolly bodies
D
TOF. RBCs are often mistaken for amebic cysts, especially those of Entamoeba histolytica, whose average size range is 12 to 18 µm
F (WBC)
WBCs are usually present in patients suffering from :
A. ulcerative colitis
B. bacterial dysentery
C. intestinal amebiasis
D. All
D
This cell have a two- to four-lobed nucleus, similar in appearance to the E. histolytica nucleus
WBC
TOF. Protozoan nuclear inclusions, such as karyosomes and peripheral chromatin, are ABSENT in WBCs
T
this ingest polymorphonuclear WBCs
macrophages
Thick-walled grains resemble the eggs of Taenia spp. but are smaller.
pollen grains
- Pollen grains may appear round or symmetrically lobed.
- Unlike Taenia, there are no notable interior structures.
Which of the following findings can help differentiate WBCs from amebic cysts?
A. Size
B. Number of nuclei
C. Absence of protozoan nuclear inclusions
D. None of the above
C. Absence of protozoan nuclear inclusions
- may easily be confused with helminth eggs.
- These cells are typically large and roundish oval to irregularly round in shape.
- Thick cell walls are usually present.
- The interior portion of vegetable cells is unorganized and often appears to consist
primarily of large vacuoles.
vegetable cells
- often resemble helminth larvae in their shape and size.
- Unlike helminth larvae, however, vegetable spirals do not have a head or tail
region. - are readily distinguished from parasitic forms by their ladder-like appearance.
- The ladder consists of a series of rungs that are spaced closely together.
Vegetable spirals
Which of the following characteristics can help differentiate vegetable
spirals from helminth larvae?
A. Presence of head or tail region
B. Ladder-like appearance
C. Characteristic worm shape
D. Length of spiral
B
- most clinically significant.
- Due to EOSINOPHIL breakdown products.
- They are typically found in stool or sputum specimens and are reported when
seen. - Demonstration of these diamond-shaped crystals indicates IMMUNE RESPONSE
of unknown origin. - such an immune response may be caused by the presence of parasite.
Charcot-Leyden Crystals
- round to oval
- may be confused with protozoan cysts,
especially those of Entamoeba hartmanni
Endolimax nana and Entamoeba hominis. - It also resembles the oocyst of
Cryptosporidium. - yeast cells typically show no definite internal
structures. - small granules resembling karyosomes may be
seen. - may be easily distinguished from parasites
when seen in their budding stage.
Yeast
- What is the clinical significance of the presence of Charcot-Leyden
crystals in a stool or sputum specimen?
A. Indicative of an immune response of unknown origin
B. Indicative of a parasitic infection
C. Indicative of a bacterial infection
D. Not a significant finding
A
- may resemble helminth larvae in size and shape.
- may appear to have a nondescript internal
structure. - does not have diagnostic structures, such as a
buccal cavity, esophagus, intestine, or genital
primordium. - There is no head or tail region.
plant hair
- resemble helminth eggs
particularly an unfertilized Ascaris
lumbricoides. - typically, round to oval in shape
and may or may not have a
definite cell wall. - often rough in appearance and
may have hairs (pseudocilia)
extending from its periphery. - The interior of the cell looks like a
cluster of odd-shaped vacuoles.
Plant material
- Plant material differs from a helminth eggs in that plant material may
have peripheral pseudocilia.
A. True
B. False
A
- show a striking resemblance to amebic trophozoites in size and shape.
- have a single nucleus and often show a distinct cell wall, just like those of the
amebic trophozoites. - lack the typical amebic trophozoite interior structures.
Epithelial cells
- may be similar to the size and shape of protozoan cysts
- The lack of interior structures easily distinguishes these artifacts from parasitic forms.
Fungal elements
- Which parasite may be confused with epithelial cells because of
their similar size and shape?
A. Helminth eggs
B. Plasmodium spp.
C. Amebic trophozoites
D. Dientamoeba fragilis
C
- also referred to as starch granules.
- Round to irregular round-shaped starch cells.
- may appear at first glance to be protozoan cysts, particularly those of E.
hartmanni and E. nana. - are readily differentiated from parasitic forms because they lack internal
structures. - nondescript mass located inside the cell is often present and may resemble a
nucleus. - no karyosome or peripheral chromatin is present.
- may be differentiated from parasites because of their dark blueblack appearance
when stained with iodine
Starch cells
- often appear on Giemsa-stained blood film smears and may be mistaken for
malarial parasites, especially the young trophozoite form. - Unlike a malarial parasite, which typically appears as a blue cytoplasm with a red
chromatin, clumped or fused platelets appear in various shades of purple.
Clumped or fused platelets
The major feature that distinguishes starch cells from protozoan cysts
is which of the following?
A. Presence of bacteria in the cytoplasm
B. Unusually large size
C. Shape
D. Lack of defined internal structures
D
- Giemsa-stain precipitate may be visible on blood smears and may be mistaken
for malarial parasites. - usually bluer in color than malarial parasites and varies in size and shape.
Stain precipitate
- such as Howell - Jolly bodies or Cabot’s rings, may be present on
Giemsa-stained blood smears - These abnormalities may be easily distinguished from malarial
parasites by their different staining characteristics.
Red cell abnormalities
TOF. * Seeing few meat fibers in DFS does
not necessarily means abnormalities.
T
seen in Creatorrhea
- Common crystal found in urine
- Often seen in feces
- CONTAMINANT from the urine
Calcium Oxalate crystal
May be mistaken from amoeba
Air bubble and oil bubble
Resemble egg of hookworm
* SIZE – important aspect of
identification
mite egg
- Which of these characteristics distinguish(es) stain precipitate from
malarial parasites?
A. Color
B. Size
C. Shape
D. More than one: ___________ (specify)
ABC
