Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
18 Cards in this Set
- Front
- Back
|
If you have the choice to send a specimen or a swab of a specimen to the lab which should you chose?
|
SPECIMEN!!!
|
|
|
How much fluid does a swab contain?
|
150 micro liters
|
|
|
Which organism, gram - or + retains dye complex?
|
positive
|
|
|
VIP
Describe in detail the Gram stain procedure. |
Steps:
1. place cells on slide 2. add primary stain - crystal violet - stains both gram - and + purple 3. iodine is used a modent to set the first dye 4. decolorizer alcohol or acetone is added - this causes the gram (-) to become colorless while positive stays + 5. Safranin counterstain, which stains everything red, is added. Gram + stay purple while - become pink |
|
|
VIP
What is the best speciman to collect for performing direct examination? |
TISSUE
|
|
|
Can you use the Gram stain to observe the presence of inflammatory cells?
|
YES (p5)
|
|
|
VIP
What is the clinical utility of a gram stain? |
Direct examination of clinical material to make an initial diagnosis.
|
|
|
Can you determine the quality of a specimen by using a gram stain?
|
Yes
|
|
|
Can you suggest an unusual organism and provide early presumptive bacterial identification using a gram stain?
|
Yes
|
|
|
Can you verify the clinical relevance of the culture using a gram stain?
|
Yes
|
|
|
What is a poor quality respiratory specimen? Why?
|
One with large numbers of squamous cells. Why? Because there are no squamous cells in the lower respiratory tract. This "sputum" really just contains spit.
|
|
|
VIP
What are acid-fast stains? |
Stains that use heat or detergent to drive stain into the cell. Once in the cell it resists decolorization. It is designed to stain bacteria with cell walls containing long chain fatty acids.
|
|
|
VIP!!
What four bacteria do acid-fast stains stain? |
mycobacteria
nocardia cryptosporidia cyclospora |
|
|
VIP
List the special fungal stains (4 types) and what they stain: |
1. Lactophenol cotton blue
- allows you to see structures clearly 2. Gomori methenamine silver - yeast cells and hyphae - pneumocystis carinii - blastomyces dermatitidis 3. Periodic acid-Schiff (PAS) - yeast cells and hyphae - Aspergillus in lung - blastomyces dermatitidis 4. Mucicarmine (mucin) - cryptococcus capsule |
|
|
What are silver stains, Warthin-Starry or Steiner, used to see? (2)
|
Bacteria and spirochetes
|
|
|
What four stains are used to ID parasites?
|
1. Wright's giemsa - malaria
2. wet mounts 3. trichrome - parasites in feces 4. modified acid fast |
|
|
How do fluorescent stains work?
|
Fluorophores absorb energy from UV wavelength and become excited. They then emit visual energy in wavelengths that can be measured. Uses dye and filters on microscope
|
|
|
VIP
What are the three flourescent stains and what do they look for? |
1. Auramine-rhodamine - VIP for mycobacteria - VIP
2. Calcofluor white stain - for fungi 3. Flurescein conjugated antibodies - for virus', bordetella, legionella, and pneumocystis |
