SPECIMEN COLLECTION & PROCESSING Flashcards
[sputum]
specimens needed for Mycobacterium
3 separate early morning specimens
These media usually contain substances that do not promote multiplication of microorganisms but ensure their preservation and are available in swab collection systems
holding / transport media
____________ to provide the larger iodine element to replace the smaller chloride in the stain molecule
gram’s iodine
specimens needed for bacterial infection
3 specimens in 3 consecutive days
[anticoagulants]
should not be used for microbiology specimens
- citrate
- ethylenediamine tetraacetic acid (EDTA)
[stains]
________________ are directed toward coloring specific components of the elements present
differential stains
bacteria with thinner walls containing lipopolysaccharides do not retain the dye complex
Gram-negative bacteria
[Acid-Fast Staining of Mycobacteria]
results:
Mycobacteria stain bright orange
fluorescent stain
[wounds/lesions after collection]
should be placed into a _________ or
____________
sterile tube or transport vial
[isolation techniques]
- The specimen is applied by _________ or placing a ___________ onto a small area at the edge of the plate
- The ____________ is sterilized and allowed to cool thoroughly before streaking the agar
- The __________________ is useful for most specimen
- The relative number of organisms can be estimated based on the extent of ________ beyond the original area of inoculum
- Growth in the first quadrant can be graded as _____________; growth in the second or third quadrant can be graded as ______________; and growth in the third or fourth quadrant can be graded as ______________
- rolling the swab, drop of liquid specimen
- inoculating loop
- general-purpose isolation streak
- growth
- 1+ or light growth; 2+ to 3+ or moderate growth; 4+ or heavy growth
Specimens for parasite microscopic studies should be collected ____________________
before any barium studies are done
This system contains selective agar and a carbon dioxide (CO2)-generating tablet
JEMBEC system
[anticoagulants]
The concentration must not exceed _______ (wt/vol) because some Neisseria spp. and certain anaerobes are inhibited by higher concentrations
0.025%
[matching type|Gram-positive cocci]
Streptococcus, Peptostreptococcus spp.
a. pairs
b. tetrads
c. clusters
d. chains
e. encapsulated
f. gram-positive diplococci (lancet-shaped)
g. gram-negative diplococci pathogenic
d. chains
[smears from thick, granular, or mucoid materials]
Granules within the material must be _________ so that their makeup can be assessed
crushed
[Rapid Modified wright-Giemsa Stain]
The Wright-Giemsa stain is available in a modification that requires only _______ minutes
1-3 minutes
[matching type|Gram-positive cocci]
Streptococcus pneumoniae, Streptococcus pyogenes (rarely), Stomatococcus mucilaginosus
a. pairs
b. tetrads
c. clusters
d. chains
e. encapsulated
f. gram-positive diplococci (lancet-shaped)
g. gram-negative diplococci pathogenic
e. encapsulated
separates double-stranded DNA
denaturation
[anticoagulants]
most common anticoagulant used for microbiology specimens
sodium polyanethol sulfonate (SPS)
anneals primers to target DNA
primer annealing
the exact anatomic site must be provided for?
wounds/lesions
specimens commonly obtained by the patient
- urine
- sputum
- stool
[preservatives]
used in commercial products to maintain accurate urine colony counts
boric acid
Plates are inoculated using a ___________ to deliver a specified volume
calibrated loop
commonly used transport medium
Stuarts’s or Amie’s transport medium
[stains]
____________ are directed toward coloring the forms and shapes present
simple stains
[true or false]
Specimens received on swabs can be inoculated directly to culture media
true
When ethidium bromide is irradiated with UV light, it fluoresces _____________
bright orange
[stains]
_______________ are directed specifically at identification of an organism
DNA probe-mediated stains
(diagnostic antibody)
[search for microorganisms]
Organisms should be evaluated for _____, _____, and _____________
shape, size, gram reaction
[These specimens should be stored in what temperature?]
- abscess, lesion, wound
- body fluids
- CSF (bacteria)
- ear (inner)
- feces (preserved)
- genital
- nasal, throat, N/P
- urine (preserved)
Room temperature
[incubation]
_______ grow in ambient air, whereas _________ cannot grow in the presence of oxygen and require an anaerobic atmosphere
aerobes, anaerobes
[incubation]
Most bacteria cultures are incubated at _____ to ______
35° C, 37° C
used to prevent clotting of specimens, including blood, bone marrow, and synovial fluid
anticoagulants
specimens needed for parasitic infection
3 samples within 10 days
[catheter]
allow _______ to pass then collect the remainder urine
15 mL
[smears from thick, granular, or mucoid materials]
Granules that are too hard to crush between two glass slides probably _____________
do not represent infectious materials
[wounds/lesions]
collected by ____________ rather than by ________
needle aspiration, swab
The two single-stranded nucleic acid molecules used in hybridization techniques are referred to as _______ and _______
target, probe
[blood culture]
mL to collect for adults
20ml
(10mL aerobic & 10 mL anaerobic)
[blood culture]
mL to collect for children
10mL
(5mL aerobic & 5mL anaerobic)
smears from swabs are prepared by __________________ over contagious areas of the glass slide to deposit a thin layer of sample material
rolling the swab back and forth
[smears from thick, granular, or mucoid materials]
It is most desirable to have both _____ and _____ areas
thick, thin
[urine]
three methods in collecting urine
- clean catch midstream
- catheter
- suprapubic aspirate
not ideal method for urine collection
catheter
appropriate for specimens from the upper respiratory tract, external ear, eye, and genital tract
swabs
[stains]
four (4) stains
- gram
- acid-fast
- calcofluor white
- rapid modified Wright-Giemsa
[search for microorganisms]
A _____ or _____ lens is preferred for scanning, and a _______ lens is used for final evaluation
x40 or x60, x100
best specimen method for urine culture
clean catch midstream
[anticoagulants]
often used for viral cultures and for isolation of Mycobacterium spp. from blood
heparin
[matching type|Gram-positive cocci]
Neisseria spp., Moraxella catarrhalis
a. pairs
b. tetrads
c. clusters
d. chains
e. encapsulated
f. gram-positive diplococci (lancet-shaped)
g. gram-negative diplococci pathogenic
g. gram-negative diplococci
[matching type|Gram-positive cocci]
Staphylococcus, Streptococcus, Enterococcus spp.
a. pairs
b. tetrads
c. clusters
d. chains
e. encapsulated
f. gram-positive diplococci (lancet-shaped)
g. gram-negative diplococci pathogenic
a. pairs
not recommended for collection
swabs
gram stain was developed empirically by the Danish bacteriologist _____________ in ______
Christian Gram, 1884
[sputum]
collection methods for sputum
expectorated or induced
Tissues can be prepared for culture by ____________, in which the tissue is ground in a tissue grinder
homogenization
[incubation]
Some bacteria are capnophiles and require an increased concentration of CO2; this can be achieved by a ________, a __________, ____, or ______
candle jar, CO2 incubator, jar, bag
[smears from thin fluids]
The cytocentrifugation process deposits __________ and ____________ from the specimen onto the surface of a glass slide as a monolayer
cellular elements, microorganisms
a technique used to separate biological macromolecules, such as nucleic acids and proteins
electrophoresis
Urine specimens are inoculated using a __________________
quantitative isolation
[matching type|Gram-positive cocci]
Staphylococcus, Peptostreptococcus, Stomatococcus spp.
a. pairs
b. tetrads
c. clusters
d. chains
e. encapsulated
f. gram-positive diplococci (lancet-shaped)
g. gram-negative diplococci pathogenic
c. clusters
inoculated plates must be incubated anaerobically at ______ to _______
35°C to 37° C
[stains]
Stains can be categorized as _______, ________, __________
simple stains, differential stains, probe-mediated stains
Bacteria with thick cell walls containing teichoic acid retain the crystal violet–iodine complex dye after decolorization and appear deep blue
Gram-positive bacteria
[urethra]
Flexible swab inserted ______ for ________
2-4cm, 2-3 secs
[nasal]
insert premoistened swab ______ into nares
1 inch
[matching type|Gram-positive cocci]
Micrococcus, Staphylococcus, Peptostreptococcus spp.
a. pairs
b. tetrads
c. clusters
d. chains
e. encapsulated
f. gram-positive diplococci (lancet-shaped)
g. gram-negative diplococci pathogenic
b. tetrads
[Acid-fast Staining of Mycobacteria]
The primary stain binds to ____________ in the cell walls of the mycobacteria and is retained after the decolorizing step with __________
mycolic acid, acid alcohol
_____________ damages these thin lipid walls and allows the stain complex to wash out
decolorizer (alcohol-acetone)
most sterile method in urine collection
suprapubic aspirate
[levels of specimen prioritization]
level 3
- catheter tip
- urine
- tissue for quantitation
[Acid-Fast Staining of Mycobacteria]
different types of stains
- Fluorescent stain
- Kinyoun stain
- Modified Kinyoun stain (Partial Acid-Fast)
- Ziehl-Neelsen stain
[smears from thin fluids]
__________________ is preferred for this type of specimen, if available
cytocentrifugation
[body fluids]
mL to collect for CSF viral studies
> 1mL
The tips of swabs may contain ______, _________, or __________
cotton, Dacron or calcium alginate
[levels of specimen prioritization]
level 1
- amniotic fluid
- blood
- brain
- cerebrospinal fluid
- heart valves
- pericardial fluid
[body fluids]
mL to collect
> 1mL
[blood culture]
used to isolate anaerobic blood culture
anaerobic blood culture
[smears from thin fluids]
“Thin” specimens of fluids such as urine, cerebrospinal fluid (CSF), and transudates should be _________ but not ________ on the slide
drop, spread
synthesizes new strands of DNA
primer extension
__________ tend to have excessive fatty acids, which may be toxic to certain bacteria
cotton-tipped swabs
a compound made from seaweed
agarose
[eye: conjunctiva]
collect using ___________ moistened with ___________ on both eyes
separate swabs, sterile saline
[Acid-Fast Staining of Mycobacteria]
results:
Mycobacteria stain red, whereas the background material and non–acid-fast bacteria stain blue
Kinyoun & Ziehl-Neelsen stains
[Rapid Modified Wright-Giemsa Stain]
results:
- Blood cells stain as with Wright stain.
- The cytoplasm is __________.
- The chromatin of white cells is ________.
- Bacteria are _______.
- Parasitic protozoan nuclei are _______.
- basophilic
- purple
- blue
- red
four (4) levels of specimen prioritization
- critical / invasive
- unpreserved
- quantitation required
- preserved
[Nucleic Acid Hybridization Techniques]
_________________ is also called duplex formation
hybridization process
____________ to color all cells and background material a deep blue
crystal violet (hexamethyl-p-rosaline chloride)
sterile containers except for stool specimens, which can be collected in ______, _________ containers
clean, leakproof
[levels of specimen prioritization]
level 4
- feces in preservative
- urine in preservative
- swabs in holding medium (aerobic & anaerobic)
[incubation]
______________ grow with reduced oxygen and increased CO2 and can be isolated using jars or bags
microaerophiles
[other stains]
It binds to the nucleic acid of the cell and fluoresces as a bright orange when a fluorescent microscope is used
acridine orange
[other stains]
a fluorochrome dye that stains both gram-positive and gram-negative bacteria, living or dead
acridine orange
[matching type|Gram-positive cocci]
Streptococcus pneumoniae
a. pairs
b. tetrads
c. clusters
d. chains
e. encapsulated
f. gram-positive diplococci (lancet-shaped)
g. gram-negative diplococci pathogenic
f. gram-positive diplococci
[The routine primary plating media include the following items]
- __________ agar plate
- _______ medium for fastidious organisms for normally sterile body fluids or a site in which fastidious organisms are expected
- ________ and ________ medium for enteric gram-negative bacilli for most routine bacterial cultures
- _________ medium for gram-positive organisms for specimens in which mixed gram-positive and gram-negative bacteria are found
- Additional _________ or ___________ for specific pathogens as needed
- ___________ may be used as a supplement with specimens from sterile body fluids, tissues, lesions, wounds, and abscesses
- nonselective
- enriched medium
- selective, differential
- selective
- selective media, enrichment broth
- broth medium
aspirate fluid with ________ if eardrum is intact
needle
[blood culture]
used to isolate aerobic bacteria
aerobic blood culture
The most common nucleic acid stain used after separation by agarose gel electrophoresis is ________________
ethidium bromide
__________________ is used to separate RNA and DNA
agarose gel electrophoresis
[true or false]
stool specimens can be refrigerated
true
[body fluids]
mL to collect for CSF fungal studies
> 2mL
[body fluids]
mL to collect for CSF bacterial culture
> 1mL
[other stains]
appear green within pink-appearing or red-appearing bacterial cells
endospore stain: Schaeffer-Fulton
[smears from swabs]
smears should not be prepared from a _____ after it has been used to inoculate culture media
swab
Stools for Clostridium difficile toxin assay should be collected ______________ and can be refrigerated; if the delay is expected to be longer than 48 hours, the specimen should be frozen at _______
without a preservative, -70 degrees C
appears as a white chalky substance in the specimen and masks the appearance of parasites under the microscope
barium
[other stains]
used to locate bacteria in blood cultures and other specimens where discerning bacteria might otherwise be difficult
acridine orange
[other stains]
DNA stain
acridine orange
two (2) types of blood culture
- aerobic
- anaerobic
[Rapid Modified wright-Giemsa Stain]
This neutral dye is a combination of basic ___________ and ________that attach to oppositely charged sites on proteins. The results are ____________
thiazine dye, eosin, metachromatic
use _______ if eardrum is ruptured
swab
[smears from thick liquids / semisolids]
The swab is _________ in the specimen for several seconds and used to prepare a thin spread of material on the glass slide for staining and viewing.
immersed
[specimen preparation]
- Specimens such as sterile body fluids, pus, urine, and sputum are ____________ onto selected media
- Large volumes of sterile body fluids are __________ to increase the recovery of bacteria.
- If the volume of fluid is greater than 1 mL, the specimen can be centrifuged for ________ at ________
- If the specimen consistency is thin enough to avoid filter clogging, filtration with a _____________ can be performed
- After filtration, the filter is removed and placed on the surface of an ________
- inoculated directly
- concentrated
- 20 min, 3000 x g
- Nalgene filter unit
- agar plate
[incubation]
Most routine bacterial cultures are held for ___ to _______
48 to 71 hours
specimens that need to be refrigerate
- catheter tips (IV)
- CSF (viruses)
- ear (outer)
- feces (unpreserved)
- sputum
- urine (unpreserved)
used to isolate bacteria from blood
blood culture
If cerebrospinal fluid is not processed immediately, it can be stored in a _______ incubator for ________
35 degrees C, 6 hours
[blood culture]
disinfect using?
- alcohol
- iodine
[body fluids]
mL to collect for CSF AFB
> 2mL
All unstained elements are subsequently counterstained red by ____________
safranin dye
The specimen should be submitted on two swabs; one is used for the ___________, and the other is used to make the __________
culture media, direct smear
[inner ear]
remove debris or crust with __________
saline moist swab
[incubation]
Cultures for anaerobes and broth cultures may be held for ___ to ______
5 to 7 days
[preservatives]
if the specimen is delayed longer than 2 hours, the specimen can be added to ______________
Cary-Blair transport media
[levels of specimen prioritization]
level 2
- body fluids
- bone
- drainage from wounds
- feces
- sputum
- tissue
