CSF ANALYSIS

3rd major fluid in the body

CEREBROSPINAL FLUID

CSF is produced via ____________________ by the ____________ of each of the four ventricles of the brain

active transport secretion and filtration, choroid plexuses

CSF flows through the _________

subarachnoid space

CSF is reabsorbed by the __________ into the ________

arachnoid villi, superior sagittal sinus

rate of production:

0.3 to 0.4 ml/ min ~ 20 ml/hr

rate of production =

rate of absorption

CSF Volume Adults:

140 to 170 ml or 90 to 150 ml

CSF Volume Neonates:

10 to 60 ml

Specimen Collection

Lumbar Puncture/Lumbar tap

Cisternal Puncture

Ventricular

routine method for CSF collection

Lumbar Puncture:

Lumbar Puncture site

Between 3rd and 4th or 4th and 5th lumbar vertebrae

collected from the sub-occipital region (cisterna magna)

Cisternal Puncture:

used in infants with open fontanels

Ventricular:

CSF TUBE 1

Chemical and serological tests

CSF TUBE 2

Microbiological tests

CSF TUBE 3

Cell count

CSF TUBE 4

Microbiology ——> chemistry/serology

Low Volume CSF

Microbiology ———> hematology ————> chemistry/serology

Frozen at -15 to -30oC

CSF TUBE

Room Temp at 19 to 26 oC

CSF TUBE

Refrigerated at 2 to 8 oC

CSF TUBE

CAUSEs Hazy, turbid, milky, cloudy CSF

WBCs

Microorganisms

Protein

CAUSE Oily CSF

Radiographic contrast media

CAUSE BLOOY CSF

RBCs

CAUSE Xanthochromic CSF

Hemoglobin

Bilirubin

Carotene

Protein

Melanin

CAUSE clotted CSF

Protein

Clotting factors

CAUSE pellicle

Protein

Clotting factors

Clotting factors that causes pellicle is significant of

Tubercular meningitis

Clot formation + blood

traumatic tap

Clot formation but no blood

meningitis, Froin’s syndrome

Web-like/pine tree clot, no blood

tubercular meningitis

Pellicle formation

suppurative meningitis

most frequently performed chemical test on CSF

Protein

Normal values of protein in CSF: 6 months to adults

15 to 45 mg/dl

Normal values of protein in CSF: Newborn =

75 to 150 mg/dl

Normal values of protein in CSF: > 60 y/o =

>60 mg/dl

Normal Protein Fractions:

albumin (major),

prealbumin (2nd),

alpha-globulins (haptoglobin and ceruloplasmin),

transferrin,

tau protein: IgG and IgA

Protein Fractions not normally found in CSF

IgM, fibrinogen beta-lipoproteins

Laboratory Detection for protein

Turbidimetric Methods

Dye-binding Methods

Electrophoresis

Precipitation of proteins

Turbidimetric Methods

Turbidimetric Methods reagents

Trichloroacetic acid

Sulfosalicylic acid

reagent of choice, precipitates both albumin and globulins

Trichloroacetic acid:

precipitates albumin only unless Na2SO4 is added

Sulfosalicylic acid:

Dye-binding Methods Principle:

protein error of indicators

Dyes used on Dye-binding Methods

1) Coomassie brilliant blue G250 (red to blue)

(2) Ponceau S

Most frequently performed for Protein identification in CSF

Electrophoresis

Method of choice for tau identification

Electrophoresis

Used to detect oligoclonal bands in serum and CSF

Electrophoresis

represents systemic and neurologic involvement seen in leukemia, lymphoma, viral infections

Oligoclonal bands in both

multiple sclerosis, encephalitis, neurosyphilis, Guillain-Barre syndrome, neoplastic disorders

Oligoclonal bands in CSF but not in serum

detected using radioimmunoassay

MYELIN BASIC PROTEIN:

destruction of myelin sheath covering the axons of neurons

demyelination

Indicates demyelination

MYELIN BASIC PROTEIN

CSF-Serum Indices

CSF-Serum Albumin Index

CSF-Serum IgG Index

Evaluates BBB integrity

CSF-Serum Albumin Index

CSF-Serum Albumin Index: intact BBB

< 9:

CSF-Serum Albumin Index: damaged BBB

> 9

Determines IgG production within the CNS

CSF-Serum IgG Index

CSF-Serum IgG Index: IgG production within the CNS

> 0.77: