F2: CSF (Part 5: Tests - TUBE 3) Flashcards
What test/section in the laboratory is done in tube 3?
Hematology
What is the normal WBC count in CSF?
less than 5 cells per ul
Done if CSF is visibly clear to detect a small amount of pleocytosis
Tyndall’s Test
Tyndall’s Test
Tyndall’s test procedure
a. Hold the tube at 90°angle in direct sunlight
b. take a laser light and flash
c. ALL
d. NOTA
c. ALL
Tyndall’s Test
Negative result in tyndall’s test
Clear
Tyndall’s Test
Positive result in tyndall’s test
Very turbid
Tyndall’s Test
T or F
When consistency is clear, dilution is used
F (If clear – don’t dilute)
Tyndall’s Test
When sample is turbid, you dilute using?
WBC pipette
Hematology – Cell Count
What (2) reagents are used to dilute CSF for cell counting?
- saline
- Turk Solution
How many squares are counted for cell counting?
5 large squares
Unit for cell count
cell/cmm
What diluting fluid is used to remove RBC
3% acetic acid
What should you do if the first CSF sample was not diluted?
Just rinse the pipette
What should you do if the first CSF sample was diluted?
use same dilution (for the addition of acetic acid) as the first
Equation in Hematology
𝑇𝑜𝑡𝑎𝑙 𝑐𝑒𝑙𝑙𝑠 𝑐𝑜𝑢𝑛𝑡𝑒𝑑 − 𝑊𝐵𝐶 𝑐𝑜𝑢𝑛𝑡𝑒𝑑 = 𝑅𝐵𝐶
Cell count correction formula
- 𝑊𝐵𝐶 𝑎𝑑𝑑𝑒𝑑 = 𝑊𝐵𝐶 (𝑖𝑛 𝐵𝑙𝑜𝑜𝑑) × 𝑅𝐵𝐶 (𝑖𝑛 𝐶𝑆𝐹) 𝑅𝐵𝐶 ( 𝑖𝑛 𝐵𝑙𝑜𝑜𝑑)
- 𝑇𝑟𝑢𝑒𝑊𝐵𝐶= 𝑊𝐵𝐶𝑐𝑜𝑢𝑛𝑡𝑒𝑑 − 𝑊𝐵𝐶𝑎𝑑𝑑𝑒𝑑
Or Subtract 1 WBC per 700 RBC counted
Hematology -Differential Count steps
- Centrifuge 5-10 minutes
- Transfer supernate to another tube
- Resuspend
- Smear
- Dry 6.Stain
How many cells are typically needed for a differential count?
100 cells
How many cells might one drop of CSF contain?
As few as 3 cells
What are the normal percentages of lymphocytes and monocytes in CSF?
70 % lymph, 30 % monocytes
- increase number, or presence of any other significant cell ie neutrophil, eosinophil
Pleocytosis
T or F
differential count is done in CSF if pleocytosis is observed
T
How are very few cells in CSF reported?
cells per slide
A differential count is not accurate in CSF with very few cells since there are (too many/ too few cells)
too few cells to perform differential
- More accurate
- Add 0.1 ml of CSF and 1 drop of 30% albumin
- cells forces onto 6 mm monolayer, stain
- Uses only 1 objective
- NOt used anymore
- Used to concentrate any body fluid
Cytocentrifuge
Cytocentrifuge
Cytocentrifuge
a. 0.1 ul of CSF
b. 1 drop of 30% albumin
c. ALL
d. NOTA
b. 1 drop of 30% albumin
a. 0.1 ul of CSF - should be 0.1 ml of CSF
T or F
Cytocentrifuge uses 2 objectives since sample is not easily seen
F (only uses 1 slide since sample is easily seen)
T or F
Differential Count may now be done using Body Fluid Analyser found in CM section
T
CLINICAL CORRELATION
Determine character
Bacterial: Increase
Viral: Increase
TB: Increase
Fungal: Increase
WBC
Determine character
Bacterial: Marked increase
Viral: Moderate increase
TB: Marked increase
Fungal: Moderate increase
Protein
Determine character
Bacterial: Marked decrease
Viral: Normal
TB: Moderate decrease
Fungal: Normal or mild decrease
Sugar
Determine character
Bacterial: >35 mg/dL
Viral: Normal
TB: >25 mg/dL
Fungal: >25 mg/dL
Lactate
Determine character
Bacterial: Phadebact CRP
Viral:
TB: Pellicle
Fungal:
Other
