CSF Flashcards
3rd major body fluid
CSF
Functions of CSF
Supply nutrients to nervous system, remove metabolic waste, cushion brain and spinal cord
Meninges 3 layers
Dura mater, Arachnoid mater, Pia mater
Outer layer of meninges
Dura mater
Filamentous inner membrane
Arachnoid mater
CSF flow space
Subarachnoid space
Innermost meninges layer
Pia mater
Reabsorption of CSF
Arachnoid villi
CSF production and reabsorption rate
20 mL/hr
CSF production site
Choroid plexus
Protects brain from harmful substances
Blood-brain barrier
CSF collection volume with manometer
20 mL
Normal CSF pressure
50-180 mmHg
CSF collection volume for high/low pressure
1-2 mL
CSF collection method
Lumbar puncture (L3-L4 adults)
CSF collection site in infants
L4-L5
CSF Tube 1 storage
Freezing temp for chemistry/serology
CSF Tube 2 storage
Room temp for microbiology
CSF Tube 3 storage
Ref temp for hematology
CSF Tube 4 use
Microbiology/Serology
Least affected tube by contamination
Tube 1
Tube for additional testing
Tube 4
Excess CSF handling
Freeze until further testing
Single CSF tube allocation priority
Micro > Hema > Chem/Sero
CSF total volume in adults
90-150 mL
CSF total volume in neonates
10-60 mL
Hazy/Milky/Turbid CSF indicates
Increased WBCs, RBCs, lipids, protein, microorganisms
Xanthochromic pink color
Slight oxyhemoglobin
Xanthochromic yellow color
Oxyhemoglobin to bilirubin
Xanthochromic orange color
Heavy hemolysis
Carotene, Melanin, Protein (>150 mg/dL), Rifampin causes what color in CSF
Xanthochromic
Bloody appearance of CSF is due to
RBCs (>6,000/uL), Traumatic tap, Intracranial hemorrhage
Indications of traumatic tap
Uneven blood distribution in tubes, Clot formation, Clear supernatant
Indications of intracranial hemorrhage
Even blood distribution, Xanthochromic, Erythrophage (hematoidin and hemosiderin), Positive D-dimer
Clinical significance of oily CSF
Radiographic contrast media
Clinical significance of clotted CSF
Protein, Clotting factors, Meningitis, Froin syndrome, CSF circulation blockage
Pellicle appearance in CSF
Tubercular meningitis
CSF cell count timing
Immediately or within 1 hour at room temperature
Percentage of WBCs disintegrating within 1 hour
0.4
Normal WBC count in adult CSF
0-5 WBCs/uL
Normal WBC count in neonate CSF
0-30 WBCs/uL
CSF dilution for clear fluid
Undiluted
CSF dilution for slightly hazy fluid
0.04861111111111116
CSF dilution for hazy fluid
0.05555555555555558
CSF dilution for slightly cloudy fluid
1:100
CSF dilution for cloudy/slightly bloody fluid
1:200
CSF dilution for bloody/turbid fluid
1:10,000
Formula for CSF WBC count
cells counted x dilution/area x depth (0.1)
CSF diluting fluid
3% acetic acid with methylene blue
Cleaning nondisposable chamber for CSF counting
Soak in bactericidal solution 15 mins; rinse with water; clean with isopropyl alcohol
WBC correction for every 700 RBCs
Subtract 1 WBC
Total protein correction for every 10,000 RBCs/uL
Subtract 8 mg/dL
Total protein correction for every 1,200 RBCs/uL
Subtract 1 mg/dL
CSF smear preparation
Concentrate specimen before smearing
Methods for CSF differential count
Cytocentrifugation, Centrifugation, Sedimentation, Filtration
Monolayer cell diameter during CSF cytocentrifuge
6 mm
CSF additive for cell yield/recovery
30% albumin
Predominant cells in CSF
Lymphocytes and monocytes
Adult lymphocyte-to-monocyte ratio in CSF
70% lymph, 30% mono
Neonate cell ratio in CSF
80% monocytes, 20% lymphocytes
Increased number of normal cells in CSF
Pleocytosis
Significance of lymphocytes and monocytes in CSF
Normal, Viral/TB/Fungal meningitis, Multiple sclerosis
Significance of neutrophils in CSF
Bacterial meningitis, Early viral/TB/fungal meningitis, Cerebral hemorrhage
Significance of eosinophils in CSF
Parasitic/fungal infections, Coccidioidal meningitis, Medications, Shunts
Significance of macrophages in CSF
RBCs in spinal fluid, Contrast media
Blast forms in CSF indicates
Acute leukemia
Plasma cells in CSF clinical significance
Multiple sclerosis
Ependymal, choroidal, spindle-shaped cells clinical significance for CSF
Diagnostic contamination
Malignant cells in CSF indicates
Carcinoma or leukemia
Normal values of CSF protein in adults
15-45 mg/dL
Normal values of CSF protein in infants
<150 mg/dL
Normal values of CSF protein in immature
<500 mg/dL
Protein is increased in CSF during
Meningitis, hemorrhage, trauma, multiple sclerosis
Decreased protein in CSF indicates
Increased CSF flow or leakage
Major CSF protein
Albumin
Second most prevalent protein in CSF
Prealbumin
Alpha-globulins in CSF
Haptoglobin, ceruloplasmin
Beta-globulins in CSF
Transferrin
Gamma-globulin in CSF
IgG
Not normally found in CSF
Fibrinogen
Preferred method for CSF total protein
Turbidimetric (Coomassie Brilliant Blue)
To precipitate globulins, add
Ammonium sulfate
Coomassie Brilliant Blue positive reaction indicates
Protein presence
CSF/Serum albumin index is used for
Assessing blood-brain barrier integrity
CSF/Serum albumin index formula
CSF albumin (mg/dL) / Serum albumin (g/dL)
Normal value of CSF/Serum albumin index
<9
CSF/Serum albumin index: 9-14
Mild impairment
CSF/Serum albumin index: 15-100
Moderate impairment
CSF/Serum albumin index: >100
Severe impairment
CSF/Serum albumin index: Complete damage to BBB
> 100
IgG index is used for CSF
Detecting IgG production within CNS
Normal value of IgG index
0.3-0.7
Abnormal IgG index
> 0.7
Detection of oligoclonal bands in gamma region indicates
Immunoglobulin production
Valuable for the diagnosis of Multiple Sclerosis
CSF electrophoresis
Better resolution in CSF electrophoresis is obtained using
Immunofixation or isoelectric focusing
Oligoclonal banding in CSF but NOT in serum
Multiple sclerosis
Oligoclonal banding in serum but NOT in CSF
Systemic infection or inflammation
Oligoclonal banding in both serum and CSF
CNS infection
Protein component of lipid-protein complex insulating nerve fibers
Myelin basic protein (MBP)
Presence of MBP in CSF indicates
Destruction of myelin sheath, Multiple sclerosis
Method for MBP detection
Immunoassay
Demyelinating disorder findings
Increased MBP, IgG index, oligoclonal bands
Specimen for blood glucose should be drawn
Simultaneously with CSF sample
Normal values of CSF glucose
50-80 mg/dL or 60-70% of plasma glucose
Decreased CSF glucose is seen in
Bacterial, fungal, or tubercular meningitis
Viral meningitis plasma glucose and CSF lactate levels
Normal glucose, lactate <25 mg/dL
CSF lactate is ___ to glucose
Independent
Sensitive method for evaluating antibiotic therapy
CSF lactate measurement
Normal values of CSF lactate
10-22 mg/dL
Increased CSF lactate is seen in
Bacterial, fungal, tubercular meningitis, cerebral ischemia
Product of ammonia and alpha-ketoglutarate
Glutamine
Normal value of CSF glutamine
8-18 mg/dL
Indirect test for excess ammonia in CSF
Glutamine measurement
Increased CSF glutamine is seen in
Reye syndrome, hepatic encephalopathy
CSF enzymes
LDH, AST, ALT, CK
LDH isoenzymes in CSF
LDH1 and LDH2
CSF LDH pattern for bacterial meningitis
Increased LDH1 and LDH2
CSF detection of bacterial antigens
Latex agglutination, immunoassays
Recommended by CDC for neurosyphilis detection
VDRL test
Predominant WBC in bacterial meningitis
Neutrophils
Protein and lactate increased in CSF indicates
Bacterial or fungal meningitis
Predominant cells in viral meningitis
Lymphocytes
Increased protein in CSF indicates
Bacterial, fungal, tubercular meningitis
Tubercular and fungal meningitis predominant WBC in CSF
Lymphocytes and monocytes
Classic starburst pattern in CSF
Cryptococcus neoformans
Agents of viral meningitis
Enterovirus, Herpes simplex, Mumps virus
Detection of Gram-negative endotoxin in fluids/instruments
Limulus amoebocyte lysate test
Reagent for Limulus amoebocyte lysate
Amebocyte extract
Principle of Limulus amoebocyte lysate
Gel-clot formation in presence of endotoxin
