Lesson 9 Flashcards
Are critical considerations, because any result the laboratory generates is limited by the quality of
the specimen and its condition on arrival in the laboratory
Specimen collection, handling, and transport
Is the most common
form of skin cleansing before drawing blood for culture.
70% alcohol followed by an idophor
Where do we use the 2 swabs that we collected?
- Direct Smear
- Culture Media
They are not recommended for routine collection
Swabs
Are recommended rather
than the cotton-tipped.
Dacron or Calcium Alginate Swabs
It must be provided on the specimen
label
Patient’s Information
The term _____ is not an appropriate specimen label, and the exact anatomic site must be provided.
Wound
All rejected specimens require a __________ to the person in charge of collecting the specimen
Phone Call
Enumerate the reasons for specimen rejection
- The information on the label does not match the information on the
requisition slip. - The specimen is transported at the improper temperature.
- The specimen has not been transported in the proper medium.
- The quantity of specimen is insufficient for testing (QNS).
- The transport of specimen exceeds 2 hours post-collection and the
specimen has not been preserved properly. - The specimen is preserved in a fixative (formalin).
- The specimen has already dried up when transported to the
laboratory. - Processing a specimen with a questionable medical value
- More than one specimen from the same source (except
blood) and from the same patient was submitted on the
same day. - A single swab was submitted with multiple requests for
various organisms. - Expectorated sputum in which the Gram stain reveals
<25 WBCs and >10 epithelial cells.
Primary goal in the transport of specimens?
to maintain the specimen as near to its original state
as possible with minimal deterioration and to prevent risk to the specimen handler.
Ideally, specimen should be transported to the
laboratory within _____ of collection.
30 minutes
For anaerobic bacteria, transport should not take more than?
10 minutes
CSF Samples must be transported within?
15 minutes
All specimen containers must be?
Leak-proof
Patient specimens or culture isolates must be _____ before being shipped.
Triple Packaged
Changes in temperature
Neisseria meningitidis and Haemophilus spp.
Changes in pH
Shigella spp.
A delay in transport causes?
A decrease in the
number of pathogens and the multiplication
of normal flora.
Stool specimens for Clostridium difficile toxin assay should be collected without a?
Preservative
It maintains the appropriate colony counts (urine) at room temperature for 24 hours
Boric Acid
Maintain the viability of microorganisms present in a
specimen but not allow multiplication.
– Examples: Stuart’s medium, Amie’s medium, Cary Blair,
Transgrow, JEMBEC
Transport/Holding Media
It absorbs fatty acids present in the specimen that could kill fastidious organisms (Neisseria gonorrheae and Bordetella pertussis).
Charcoal
It is a common stool transport medium but is not preferred because it is toxic to enteric bacteria like Vibrio and
Campylobacter.
Buffered glycerol-saline
They are used to prevent clotting of blood, bone marrow and
synovial fluid.
Anticoagulants
For blood culture media because Neisseria spp. and some anaerobic bacteria are sensitive to higher
concentrations
0.025% Sodium Polyanethol Sulfonate (SPS)
Used for mycobacteria and viral cultures; it may inhibit growth of Gram-positive bacteria and yeast.
Heparin
They should not be used for microbiology
EDTA and Citrate
Order of priority when multiple specimens arrive at the same time
- CSF
- Tissues
- Blood
- Sterile Fluids
What are the examinations that are not performed in the Direct Microscopic Examination?
Throat, Nasopharyngeal, and Stool Spx
For stool, if the delay is no
longer than 2 hours, the
specimen can be added to?
Cary-Blair Transport Media
Specimens suspected of
containing ______ _______
should never be stored in the
refrigerator.
Anaerobic Bacteria
