F2: CSF (Part 3: Tests - TUBE 1) Flashcards
Tube 1 includes what tests?
Chemistry and Serology
What analytes are measured in chemistry?
- Protein
- Sugar
- Lactic acid
- Enzymes
- Glutamine
Chemistry - Protein
Percentage and volume of protein in plasma
< 1% of plasma level
< 45 mg/dl
Chemistry - Protein
Protein increases with these conditions
a. Inflammation, increased permeability of BBB
b. Disintegrated cells and bacteria
c. Antibodies produced by nervous tissue
d. Obstruction of CSF flow
e. ALL
f. NOTA
e. ALL
Chemistry - Protein
What are the (4) methods of measuring protein?
- Antiquated
- Turbidimetric
- Colorimetric
- Immuno-chem
(4) methods of measuring protein
What are the 2 tests under Antiquated method of measurement of protein
- Colloidal gold
- Pandy’s
(4) methods of measuring protein
- Not done anymore
- Expensive - uses real gold
- Qualitative test
Antiquated test
Colloidal gold
(4) methods of measuring protein
- Only measures globulin
- Produced in the brain → CSF
- Does not pass brain barrier
Antiquated test
Chemistry - Protein
Pandy’s
(4) methods of measuring protein
Tests under this method is:
* TriChlorAceticacid (TCA)
* SSA
Chemistry - Protein
Turbidimetric
(4) methods of measuring protein
Tests under this method is:
* Lowry
* CBB
* Ponceau
* modified biuret
Chemistry - Protein
Colorimetric
(4) methods of measuring protein
- This method uses the most automated analyzers
Chemistry - Protein
Immuno-chem
Chemistry - Protein
(4) methods of measuring protein
Colorimetric biuret method positive and negative results?
(+) Purple
(-) Blue
Blue to purple
Chemistry - Protein
If sample is contaminated with blood….Protein level will be too high, what action must be done
Protein correction
Chemistry - Protein
In protein correction, one must subtract (blank) for (blank)
subtract 1mg/dL of protein for every 1000 RBC counted
T or F
Protein correction formula should only be used if HCT and blood protein levels are normal
T
Other CSF Proteins
What are the other (3) CSF proteins
- Alpha 2 macroglobulin (A2M)
- Fibronectin
- Transferrin (tau)
AFT AFT AFT AHUH AHUH
Other (3) CSF proteins
- Indicates Subdural hemorrhage
- Breakdown of BBB
- Not done anymore
Alpha 2 macroglobulin (A2M)
Other (3) CSF proteins
Alpha 2 macroglobulin (A2M) is now replaced by what technology?
Alpha 2 macroglobulin (A2M)
CT scan/MRI are now used
Other (3) CSF proteins
- Indicates poor prognosis in Acute Lymphoblastic Leukemia (ALL)
- No lumbar puncture done anymore
Fibronectin
Other (3) CSF proteins
- Unique to CSF
- CSF leakage
- Rhinorrhea /Otorrhea
- Used to differentiate CSF from serum
Transferrin (tau)
Chemistry – Protein Fractions
Familiarize the protein fractions
- Albumin
- Pre albumin (second most abundant in CSF)
- transferrin (tau)
- IgG (second most abundant in serum)
- IgA
- ceruloplasmin
- haptoglobin
Chemistry – Protein Fractions
↑ albumin and globulin indicates
a. BBB damage
b. CNS
c. ALL
d. NOTA
a. BBB damage
Chemistry – Protein Fractions
↑ globulin only
a. BBB damage
b. CNS
c. ALL
d. NOTA
b. CNS
Chemistry - Protein Indices
What are the (3) protein indices
- CSF/Serum albumin index
- CSF/Serum IgG index
- CSF IgG/albumin
Chemistry - Protein Indices
What is the probable cause
CSF/Serum albumin ratio: INCREASED
CSF/Serum IgG ratio: INCREASED
CSF IgG/Albumin index: NORMAL
Increased permeability of blood-brain barrier
Chemistry - Protein Indices
What is the probable cause
CSF/Serum albumin ratio: NORMAL
CSF/Serum IgG ratio: INCREASED
CSF IgG/Albumin index: INCREASED
Increased
intrathecal synthesis of proteins
Chemistry - Protein Electrophoresis
Whare the the 2 bands of comparison in protein electrophoresis?
- Serum
- CSF
Chemistry - Protein Electrophoresis
Bands in Serum and CSF indicate what (2) conditions
- Leukemia
- Lymphoma infection
Chemistry - Protein Electrophoresis
Bands in CSF indicate what (3) conditions
- Multiple sclerosis
- Encephalitis
- G-B syndrome
MEGGGGG???
Chemistry - Protein Electrophoresis
- This condition will start as a simple cold and cough
- Legs will become heavy to the point person cannot walk anymore
- If not rushed to the hospital, paralysis may take over the body and cause death
Band in CSF only
Guillain-Barré syndrome
Chemistry - Protein Electrophoresis
- Looks pretty much the same but has a darker area at the end
- A valuable tool in assessing multiple sclerosis when accompanied by increases IgG index
Unusual band
Chemistry - Protein Electrophoresis
Familiarize the possible diseases in finding oligoclonal bands in CSF
- Multiple Sclerosis
- Subacute sclerosing panencephalitis
- Viral CNS infections
- Neurosyphilis
- Guillain Barre Syndrome
Chemistry - Glucose
What percentage of blood glucose levels does normal cerebrospinal fluid (CSF) glucose typically represent?
60-70 % of blood glucose
Chemistry - Glucose
Normal volume range for CSF glucose levels
45-80 mg/dl is normal
Chemistry - Glucose
Abnormal volume range for CSF glucose levels
< 40 mg/dl is abnormal
Chemistry - Glucose
Why check blood glucose 2–3 hours before a lumbar puncture?
CSF glucose lags behind blood glucose by 30–50 minutes
Chemistry - Glucose
CSF glucose lagging time behind blood glucose
Lags 30-50 minutes
Chemistry - Glucose
What two processes cause CSF glucose to decrease?
- increased glycolysis by tissues
- increased utilization by microorganisms (except viruses).
Chemistry - Glucose
T or F
Viruses don’t decrease CSF glucose because they use nucleic acids, not glucose, for replication.
T
Chemistry - Glucose
Elevated sugar is evidence of what condition?
traumatic tap
no correction is done
Chemistry - Glucose
T or F
A correction is done when there is elevated glucose in CSF
F (no correction is done)
Chemistry –Lactic Acid
All of the following increases with lactic acid except
a. Aerobic glucose metabolism in bacterial
b. tubercular and fungal infection
c. Hypoxia
d. Xanthochromia
e. ALL
f. NOTA
a. Aerobic glucose metabolism in bacterial (should be Anaerobic glucose metabolism in bacterial)
Chemistry –Lactic Acid
At what lactic acid level in CSF is bacterial infection indicated?
Anaerobic glucose metabolism in bacterial
> 35 mg/dL
Chemistry –Lactic Acid
What lactic acid level suggests tubercular or fungal infections in CSF?
tubercular and fungal infection
> 25 mg/dL
Chemistry - Enzymes
(4) Enzymes measured
- Adenosine Deaminase (ADA)
- Creatine Kinase (CK)
- Lactate Dehydrogenase (LDH)
- Lysozyme
Chemistry - Enzymes
- Rarely requested
- PCR is done instead
- Detects Tuberculosis
(4) Enzymes measured
Adenosine Deaminase (ADA)
Chemistry - Enzymes
- Nowadays, it is not needed anymore
- Detects Severity of concussion
Chemistry - Enzymes
Creatinine Kinase
Chemistry - Enzymes
- MRI is done now instead of this
- Detects Intracranial hemorrhage and Leukemia
Lactate Dehydrogenase (LDH)
Chemistry - Enzymes
T or F
Leukemia can also be detected using LDH and PET scan
T
Chemistry - Enzymes
- Not done anymore because it can be seen in a blood smear
- Detects bacterial meningitis
Lysozyme
Chemistry - Glutamine
T or F
Glutamine is rarely requested and decreases in CSF as ammonia increases
F (Glutamine chem test is rarely requested BUT increases in CSF as ammonia increases)
Chemistry - Glutamine
(1) What happens to blood ammonia when it is elevated?
What process happens next
It crosses into the CSF “as if a gas.”
diffuses across the blood-brain barrier into the CSF
Chemistry - Glutamine
(2) How is ammonia detoxified in the brain?
Ammonia combines with α-ketoglutarate to form glutamine
NH3 + aKG ➔ glutamine
Means of NH3 removal
Chemistry - Glutamine
When glutamine increases in CSF, it is indicative of all except?
a. Reye syndrome
b. Severe kidney disease
c. >35 mg/dL causes coma
d. ALL
e. NOTA
b. Severe kidney disease (should be severe liver disease)
SEROLOGY
2 methods mentioned in serology?
- “Phadebact” or BAT
- Enzymes (Limulus Lysate, Latex Agglutination, VDRL)
SEROLOGY
- Aka Bacterial antigen test
- Expensive
- Cannot always detect the presence of diseases
- The type of infection detected are rare except for TB
- In the Philippines, it is only done in RITM
- Detects Pneumococcal, H. influenza type b, Strep B, Meningococcal
“Phadebact” Bacterial antigen test (BAT)
SEROLOGY
3 tests under serology using enzymatic method
- Limulus Lysate
- Latex Agglutination
- VDRL
Serology - Enzymes
- detects endotoxins produced by gram-negative bacteria
- Little to no request for this exam
- Detects not the bacteria but the endotoxins only
- For gram-negative bacteria only
- Detects N. meningitidis, H. influenza type b, E. coli, Pseudomonas
3 methods
Limulus Lysate
Serology - Enzymes
- Commonly requested but not all can accommodate
- Very easy test
- If the hospital/laboratory cannot accommodate this, it is redirected to RITM
- Detects Cryptococcus neoformans
3 methods
Latex Agglutination
Serology - Enzymes
- Specific for syphilis only
- Detects syphilis
3 methods
VDRL