midterm examGERM TUBE TEST AND SPECIMEN COLLECTION Flashcards
what does germ tube test detects?
candida albicans and candida dubliniensis from other candida species
type of specimen we can use for germ tube test
human or sheep serum
we are incubating human or sheep serum in what temperature and how many hours
37*C for 2-3 hrs
what are the alternative for germ tube media
brain heart infusion broth
trypticase soy broth
nutrient broth
positive result in germ tube test
presence of germ tubes (short hyphal extension arising laterally from the yest cell with NO CONSTRICTION at the point of origin)
mukhang kutsara - positive
negative result in germ tube test
absence of germ tube - only a budding- presence of pseudohyphae
with constriction
materials needed for germ tube test
tsb
inoculating loop
alcohol lamp
glass slide
cover slip
yeast culture
procedure
using a sterile inoculating loop, pick a small amount of yeast colony from a culture plate
(3-5 colonies)
suspend the colonies in the TSB (2 tubes)
incubate at 37*C for 2hrs
after incubation place a drop of the incubated mixture on a clean glass slide and cover with cover lsip
examine the slide under the microscope
how many colonies are suspended on the tsb
3-5 colonies
Specimen collection depends on the specific disease syndrome, viral agents suspected, and the time of the year
true or false
true
In the requisition, the specimen type and suspected virus should be included.
true or false
true
Must be collected as early as possible after the onset of symptomatic disease
true or false
true
the viral load is highest or at peak on what stage
the first onset of symptomatic disease
the collectors must be notified of what type of virus or sample is to be collected to prepare an accurate PPE
t or f
true
specimens for the detection of virus should be collected as early as how many days after the first appearance of symptoms
2 days
this type of swab is not used in collection as it interfere with nucleic acid based test, recover of some enveloped viruses, and fluorescent-antibody test
Calcium alginate swabs
if we are not allowed to use calcium alginate swab, what are the recommended swabs?
dacron swab
rayon swab
flocked swab
this type of swab is made up of polyester fibers that is used during the covid 19 pandemic
flocked swab
SUCCESSFUL LABORATORY INVESTIGATIONS
✓Collection of adequate and appropriate specimens
✓Sufficient documentation
✓Biosafety and decontamination
✓Correct packaging
✓Rapid transport
✓Choice of a laboratory that can accurately
perform the tests
✓Timely communication of results
Specialized medium used to transport and
store viral sample
viral transport medium
components of VTM
buffering agent
stabilizers
antimicrobial agents
buffering agent of VTM
phosphate-buffered saline
hanks’ balanced salt solution
the phosphate-buffered saline is for __
pH stability and osmotic balance
hanks’ balance salt solution is a mixture of
salts and nutrients
stabilizers for VTM
glycerol
protein stabilizers
this stabilizer of VTM that is for preservation of viral particles
glycerol
this stabilizer is to stabilize the viral particles
protein stabilizer
example of protein stabilizer
bovine serum albumin
this antimicrobial agent that is for bacteria
gentamicin, penicillin, streptomycin
this antimicrobial agent that is for fungi
amphotericin B
this type of specimen collection are superior to swabs
aspirates
Swabs should be made of
polyester, Dacron, or rayon with plastic or
aluminum shafts
swabs are Often are contaminated with bacteria.
Contaminants may be removed by concentrating the sample through
__
centrifugation
viruses that uses throat swabs
Enteroviruses , Adenoviruses, HSV
viruses that uses Nasopharyngeal swab or aspirate
—RSV , Influenza, Parainfluenza
the virus that uses Nasal Specimen to identify
rhinovirus
In THROAT SWAB : POSTERIOR PHARYNGEAL SWAB
we are holding the tongue away with __
tongue depressor
in throat swab; posterior pharyngeal swab
we locate which areas
Locate areas of inflammation and
exudate in posterior pharynx, tonsillar
region of throat behind uvula
areas to avoid in throat swab; posterior pharyngeal swab
avoid swabbing soft palate;
do not touch tongue
buccal mucosa
teeth and gums
in NASOPHARYNGEAL ASPIRATE
we are instilling how many ml of VTM/sterile normal saline into one nostril
1-1.5ml
a process wherein we are inserting silicon catheter in nostril and aspirate the secretion gently by suction in each nostril
NASOPHARYNGEAL ASPIRATE
all respiratory specimens are acceptable for culture of most viruses. However, they are prone to contamination, to remove the contaminants, we can concentrate the sample through
centrifugation of filtration
this type of specimen collection that is for Specimen for detecting viruses that infect the lower respiratory tract (Influenza and Adenoviruses)
bronchial and bronchoalveolar washes
in bronchial and bronchoalveolar washes, we ___ to remove contaminating materials
centrifuge
centrifuging bronchial and bronchoalveolar washes to remove contaminants is not necessary if the sample are for what tests
Not necessary if sample are for antigen and nucleic acid testing
RECTAL SWABS AND STOOL are for what viruses
Used to detect Rotavirus, enteric adenoviruses (serotypes 40 and 41), and
enteroviruses.
many agents of viral gastroenteritis do not grow in cell culture and will require ___
PCR or electron microscopy for detection
Stool sample is preferable for what viruses
preferable for rotavirus and enteric adenovirus testing.
Rectal swabs - acceptable for detecting enteroviruses in patients suspected of
having an enteroviral disease, such as __
aseptic meningitis
how to get a rectal swab
insert the rectal swab 3-5 cm into the rectum and rotated against the mucosa to obtain feces
stool sample vs rectal swab, which one is preferred and why
stool sample is preferred, rectal swab has a potential for decreased viral recovery due to its small sample size
Due to bacterial contamination in stool, _____ or both are
necessary for cell cultures for the recovery of viral agents
centrifugation, filtration
sample amount of freshly passed diarrheal stool or stool collected in a diaper from young infants that is sufficient and preferred for rotavirus and enteric adenovirus detection
five to ten milliliters
5-10 ml
Storage temperature for stool and rectal samples
4C or -15C (antigen detection and PCR )
urine specimen is used for detection of which viruses
Detection of CMV, Mumps, Rubella and Measles Virus,
Polyomavirus and Adenovirus
improved recovery in urine is found in ___
at least 10 ml from clean catch first morning urine
since low yield of viruses are found in urine, we collect how many urine sample?
2-3 urine sample of 10 ml each
sterile body fluids, especially CSF and pericardial and pleural fluids, these specimen is collected by whom
physicians and sent to lab for processing
interference of urine pH and bacteria may affect viral replication
give the remedy
- Urine is centrifuged or filtered to remove contaminants and neutralizing pH with 7.5% solution of sodium bicarbonate
which viruses are can be detected in vesicular lesions of the skin and
mucous membranes.
Enteroviruses, HSV, VZV, and in rare cases CMV or pox viruses
Once the vesicle has ulcerated or crusted, detection of the virus is
___.
difficult
collection of specimens from cutaneous vesicles for the Detection of HSV or VZV may require a __ if PCR testing is not available.
herpes simplex virus
varicella zoster virus
Tzanck smear
__ are prepared by carefully unroofing the
vesicle.
Tzanck smears
sterile body fluids, especially CSF and pericardial and pleural fluids,
may contain what viruses
enteroviruses, HSV, VZV, influenza viruses, or CMV
other body fluids Must not be diluted with VTM because
it cause false negative results
viral culture of blood is primarily used to detect
CMV,
but we can still encounter HSV, and VZV, enteroviruses and adenovirus
Specimens contaminated with blood may inhibit viral cultivation due to
presence of __
antibodies
we will be able to find viruses in Amniotic Fluid such as
-congenital CMV, VZV and parvovirus B19
if there’s a delay in processing for amniotic fluid for viruses such as -congenital CMV, VZV and parvovirus B19
we must store it in
: Storage at refrigerated temp for 48hrs or -70°C if long
Viral culture of blood is used primarily to detect __
CMV
Viral culture of blood is used primarily to detect CMV; however, ____occasionally may be encountered
HSV, VZV, enteroviruses and adenovirus
__ mL of anticoagulated blood collected in a whole blood tube is
needed.
5-10
for blood viral detection, what anticoagulant is acceptable if the sample collected is to be test for nucleic acid testing
EDTA
for blood viral detection, what anticoagulant is acceptable if the sample collected is to be test for SEROLOGIC TEST and nucleic acid assays
serum
___ anticoagulated blood is acceptable for CMV detection.
Heparinized, citrated, or ethylenediaminetetraacetic acid (EDTA)
___ blood should be used for samples collected for
nucleic acid testing, because other anticoagulants may interfere with the
enzyme functions required for PCR amplification.
EDTA and Citrated
blood components that may be used for serologic tests and nucleic acid assay
Serum
for bone marrow specimen, we are using these anticoagulant for culture
heparin or edta
for bone marrow specimen, we are using these anticoagulant for nucleic acid tetsing
edta and acid citrate dextrose
this specimen is Useful for detecting viruses that commonly infect the lungs (CMV,
influenza virus, adenovirus, sin nombre virus), brain (HSV), and
gastrointestinal tract (CMV).
tissue sample
this type of sample is usually Collected during surgical procedures
tissue sample
type of tissue that is preferred for nucleic acid assays
Fresh tissue
GENITAL SPECIMENS are used for the detection of
herpes simplex virus and HPV
Genital swabs should be used for ulcerations and placed in
appropriate viral transport media.
true or false
true
Cervical specimens may be collected using a __ or __ and
placed in viral transport media.
swab or brush
__ serum specimens may be needed to detect
antibody to specific viruses.
Acute and convalescent
__ should be collected as soon as possible after the
appearance of symptoms.
Acute specimens
Appropriate specimen is __ mL of serum collected by venipuncture.
3 to 5
the convalescent specimen is collected a minimum of how many weeks after the acute specimen
2-3 weeks
