PARA LAB Flashcards
Among the specimens available for parasitic
examinations, the ______ is most commonly
utilized
stool
Stool samples should
be collected a ________ after the last intake of any drugs.
week
drugs that leave
crystalline residues
- antacids
- anti-diarrheals
- barium
- bismuth
- laxatives
A routine stool examination
usually requires a ___________
specimen of formed stool or about __________________ of watery stool.
thumb-sized, 5 to 6 tablespoons
Temporary storage of fecal samples in a refrigerator with temperature at around ______ is acceptable, but prolonged refrigeration can bring
about ____________
(3-5°C), desiccation
is an all purpose fixative
Formalin
A ____ concentration formalin is recommended for protozoan cysts, while a ______ concentration formalin is recommended
for helminth eggs and larvae
5%, 10%
The formalin solution may be buffered with _______________ to preserve the
morphological characteristics of the organisms.
sodium phosphate
is used to
preserve fresh stool in preparation for
staining the stool smears.
Schaudinn’s solution
Schaudinn’s solution contains
______________ which is highly
toxic to humans.
mercuric chloride
is a plastic resin which serves to adhere a stool sample onto a slide
Polyvinyl alcohol (PVA)
Polyvinyl alcohol (PVA) is normally
incorporated into the _________________, therefore the actual fixation is done by this fixative
Schaudinn’s solution
One major drawback of
PVA is the use of mercuric chloride. Some laboratory technologists have suggested replacing this compound
with ______________________
cupric sulfate.
It is useful for
the fixation of intestinal protozoans,
helminth eggs, and larvae
Merthiolate-iodine-formalin (MIF)
Merthiolate-iodine-formalin (MIF)
contains merthiolate (also called
thimerosal) and iodine which act as __________________, while formalin acts as the ___________________
staining components, preservative
has the advantage of not
containing mercuric chloride, however, are
not as sharp after staining compared
with those fixed in PVA or Schaudinn’s
solution.
Sodium acetate-acetic acid formalin (SAF)
It is a liquid fixative with a
long shelf-life.
Sodium acetate-acetic acid formalin (SAF)
__________________ are generally observed
in soft or liquid stool,
Protozoan trophozoites
______________________ are often
found in formed or semi-formed samples.
Protozoan cysts
____________________________ can be found in any type of consistency.
helminth eggs and
larvae
_______________________
suggests bleeding high up in the gastrointestinal
tract, while _________________ means bleeding
from a more distal location
Dark-colored blood, bright red blood
_________________________
in soft or watery stools may possibly yield the
presence of trophozoites
Blood and mucus
can reveal many
elements present in the intestinal tract aside
from parasites and normal fecal constituents
Microscopic examination
Presence of ______________________ in stool may indicate inflammation
Polymorphonuclears (PMNs)
Presence of ______________________ in stool may indicate
an immune response to a parasitic
infection
Eosinophils
Presence of ______________________ in stool may indicate
ulcerations or bleeding
Red blood cells
are released
with the disintegration of eosinophils.
Charcot-Leyden crystals
Presence of ______________________ may indicate presence of
hypersensitivity or parasitic infections,
especially amebiasis.
Charcot-Leyden crystals
This is a routine method of stool
examination primarily useful in the detection
of motile protozoan trophozoites.
Direct Fecal Smear (DFS)
in Direct Fecal Smear (DFS) About __________ of stool is
comminuted thoroughly with a drop of _____________________ and then covered with a cover slip
2 mg, 0.85% sodium chloride solution (NSS)
Trophozoites can be stained
to demonstrate the nuclear morphology using
______________________ solution.
Nair’s buffered methylene blue (BMB)