(P) Lec 5: Body Fluid Analysis (CSF)

Question 1

• This fluid occupies the spaces of the CNS (between the arachnoid and pia mater)
• It flows through the subarachnoid space and is reabsorbed in the arachnoid granulations/villi

Answer 1

Cerebrospinal Fluid (CSF)

Question 2

CSF

What structure is responsible for the formation of CSF?

Answer 2

Choroid plexus (made up of ependymal cells)

Question 3

CSF

How much CSF is produced (3 values):
- per hour
- per minute
- per day

Answer 3

• Per hour: 20mL/hour
• Per min.: 0.4mL/min.
• Per day: 480-500mL/day

Question 4

CSF

Give the total volume of CSF:
- For adults
- For neonates

Answer 4

• Adults: 90-150mL
• Neonates: 10-60mL

Question 5

CSF

Refers to the membranes covering the brain and spinal cord

Answer 5

Meninges

Question 6

CSF Functions

1. It protects and supports the ____ and spinal cord
2. Provides a medium for the transport and exchange of ____ and metabolic wastes

Answer 6

1. Brain
2. Nutrients

Question 7

CSF

Refers to a tight fitting structure of the endothelial cells in the choroid plexuses that controls the passage of substances in the blood to the brain & CSF

Answer 7

Blood-Brain Barrier

Question 8

CSF Collection

A lumbar puncture (spinal tap) is done between what vertebrae of:
- Adults
- Neonates

Answer 8

• Adults: between L3 and L4
• Neonates: L4 and L5

Question 9

CSF

In CSF collection, what are the tests performed for tubes 1, 2, 3, and 4?

Answer 9

1. Chemistry/Serology
2. Microbiology
3. Hematology
4. Cytology/Microbiology

Question 10

CSF

In CSF collection, how would you preserve tubes 1 (chemistry), 2 (microbiology), and 3 (hematology)?

Answer 10

1. Freeze
2. Room temperature
3. Refrigerate

Question 11

CSF

Which of the ff. is NOT an indication for CSF testing?
- CNS infection
- CNS hemorrhage
- Demyelinating disease
- Clotting problems within the brain vessels
- Malignancy

Answer 11

Clotting problems within the brain vessels

Question 12

CSF

What is the normal color and transparency of CSF?

Answer 12

Colorless and Clear

Indicates that the sample is free of clots and blood

Question 13

CSF

This refers to a web-like clot that is highly indicative for TB

Answer 13

Pellicle formation

Question 14

CSF

A traumatic spinal tap and subarachnoid hemorrhage will produce a sample that contains what?

Answer 14

Blood

Question 15

CSF

Traumatic Tap or Intracerebral Hemorrhage?
- Uneven distribution of blood
- Clot formation
- Supernatant is NOT xanthochromic

Answer 15

Traumatic tap

Question 16

CSF

Traumatic Tap or Intracerebral Hemorrhage?
- Even distribution of blood
- No clot formation
- Supernatant is xanthochromic
- There is erythrophagocytosis and is (+) for D-dimer
- Contains hemosiderin-laden macrophages

Answer 16

Intracerebral Hemorrhage

Question 17

CSF

Among the ff.:
- Protein
- Glucose
- Chloride
- Sodium
- Potassium, Calcium, and Bicarbonates

Which among them are lower/higher in CSF than in plasma?

Answer 17

• Lower: Protein, Glucose, K, Ca, and Bicarbonates
• Higher: Chloride and Sodium

Question 18

CSF

• Protein levels are lower in CSF than in plasma as they contain no ____
• Glucose is 2/3 the volume of ____

Answer 18

1. Fibrinogen
2. Blood sugar

Question 19

CSF

Chloride is how many percent higher in CSF than in plasma?

Answer 19

25%

Question 20

CSF

• Glucose in CSF is vital distinguishing various causes of ____
• What are the normal values of CSF glucose compared to plasma glucose?
• Blood glucose should be drawn ____ hours prior to a spinal tap

Answer 20

1. Meningitis
2. 60-70% of plasma glucose
3. 2-4 hours

Question 21

CSF

What do the ff. events cause (1 answer)?
- A disorder of the carrier-mediated transport of glucose into CSF
- There is active metabolism of glucose by cells or organisms (e.g. bacterial meningitis)
- Increased metabolism of glucose by the CNS (e.g. meningeal neoplasia & brain tumor)

Answer 21

Hypoglycorrhachia (decreased CSF glucose)

Question 22

CSF

This analyte test is maintained by the integrity of the BBB as it controls the passage of substances in the blood to the brain & CSF

Answer 22

Protein Chemical Test

Question 23

CSF

1. Give the normal value of CSF protein (CHON)
2. Is CSF protein slightly higher in infants, elderly, or middle aged adults?

Answer 23

1. 15 to 45mg/dL (0.5%-1% of plasma)
2. Higher in infants and elderly

Question 24

CSF

Give the proteins found in CSF with their descriptions:
1. The major CSF protein
2. The 2nd most prevalent protein
3. Alpha-globulins (2)
4. The major beta-globulin
5. Gamma-globulins (2)
6. A carbohydrate-deficient fraction of transferrin

Answer 24

1. Albumin
2. Prealbumin (transerythrin)
3. Haptoglobin and Ceruloplasmin
4. Transferrin
5. IgG and IgA (small amount)
6. Tau (B2 Transferrin)

Question 25

# CSF What 3 proteins are NOT normally found in CSF?

Answer 25

1. IgM 2. Fibrinogen 3. Beta-lipoprotein

Question 26

# CSF TOF: Tau (B2 Transferrin) is seen ONLY in CSF and not in serum

Answer 26

True

Question 27

# CSF Causes of INCREASED CSF protein: 1. ____ of blood 2. Increased ____ of the membrane (meningitis) 3. Increased ____ of the CNS tissue (MNS and SSPE) 4. ____ as the case with tumors and abscesses 5. A decreased rate in ____ ## Footnote Note: MS (multiple sclerosis) and SSPE (sub-acute sclerosing panencephalitis)

Answer 27

1. Lysis 2. Permeability 3. Production 4. Obstruction 5. Removal

Question 28

# CSF This is the most common inflammatory demyelinating disease of the CNS

Answer 28

Multiple Sclerosis

Question 29

# CSF Causes of DECREASED CSF protein: 1. Decreased ____ from plasma 2. Increased ____ loss 3. Leakage of CSF from a tear in the ____ leading to otorrhea or rhinorrhea

Answer 29

1. Dialysis 2. Protein 3. Dura

Question 30

# CSF What are the 2 turbidimetric methods for measuring CSF protein?

Answer 30

1. Trichloroacetic Acid (TCA) 2. Sulfosalicylic Acid (SSA)

Question 31

# CSF Turbidimetric methods for measuring protein: 1. This one is preferred because it precipitates albumin and globulin equally 2. This should be combined with sodium sulfate

Answer 31

1. Trichloroacetic Acid (TCA) 2. Sulfosalicylic Acid (SSA)

Question 32

# CSF This protein measurement method: - Allows for dyes to bind with the protein - Is faster and more accurate - Only needs a small amount - Has Coomasie Brilliant Blue as an example

Answer 32

Dye-binding Techniques

Question 33

# CSF These protein fractions: 1. Are produced in the liver and are present in the CSF because of membrane transport mechanisms 2. Are immune entities that can be produced in the CSF

Answer 33

1. Albumin 2. Immunoglobulins

Question 34

# CSF Give the ff. indices: 1. This measures the integrity of the BBB 2. Detects the production of immunoglobulin in CSF

Answer 34

1. CSF/Serum Albumin Index 2. CSF/IgG Index

Question 35

# CSF 1. In the CSF/Serum Albumin index, a ratio of ____ indicates a damaged BBB (meningitis) 2. In the CSF/IgG index, the normal value is ____ while an index of ____ suggests multiple sclerosis

Answer 35

1. > 9 2. < 0.73; > 0.77

Question 36

# CSF This is the method used for the identification of the tau isoform of transferrin

Answer 36

Electrophoresis

Question 37

# CSF What is the common medium used for CSF electrophoresis?

Answer 37

Agarose Gel

Question 38

# CSF 2 or more oligoclonal bands in CSF, but not in serum, indicate the production of ____ in the CNS

Answer 38

Immunoglobulins

Question 39

# CSF Give the ff. diseases: 1. Is only found in CSF 2. May also produce oligoclonal banding that may not be present in the serum (4) 3. Found in CSF and in the blood

Answer 39

1. Multiple Sclerosis 2. SSPE (encephalitis), neurosyphilis, Guillain-Barrésyndrome, and neoplastic disorders 3. AIDS

Question 40

# CSF This protein indicates recent destruction of the myelin sheath that protects the axons of the neurons (demyelination) and is used a marker for the progression of multiple sclerosis

Answer 40

Myelin Basic Protein (MBP)

Question 41

# CSF - This is an indicator of anaerobic metabolism within the CSF - It can distinguish bacterial from viral meningitis - Is increased in tissue destruction within the CNS (hypoxia)

Answer 41

Lactate

Question 42

# CSF What is the normal value for lactate in the CSF?

Answer 42

10-22 mg/dL (or 10-24)

Question 43

# CSF Give the type of meningitis correspondent to the lactate level: 1. > 35mg/dL 2. > 25mg/dL but < 35mg/dL 3. < 25mg/dL

Answer 43

1. Bacterial meningitis 2. Tubercular or fungal meningitis 3. Viral meningitis

Question 44

# CSF - This is produced from ammonia and alpha-keto glutarate by the brain cells - Also serves as an indirect test for ammonia in CSF

Answer 44

Glutamine | Note: Glutamine is more stable than ammonia

Question 45

# CSF What 3 conditions elevate CSF glutamine levels?

Answer 45

1. Liver disease 2. Reye's syndrome 3. Hepatic encephalopathy