CSF

Bone, meninges, and fluid

dura mater, arachnoid mater, pia mater

subarachnoid space (between the pia and arachnoid)

80-150 mL

clear liquid containing glucose, proteins, and ions

mechanial protection, chemical protection, and circulation

floats brain & softens impact with bony walls

by providing optimal ionic concentrations for action potentials

nutrients and waste products to and from the blood stream

arterial blood by choroid plexuses

tufts of capillaries with thin fenestrated endothelial cells

modified ependymal cells with microvilli

arachnoid villi (grapelike clusters of arachnoid layer)

20 ml/hr (same as production rate)

Blockage of drainage of CSF but continued production causing an increase in pressure

tumor, inflammation, developmental malformation, meningitis, hemorrhage, or injury

neurosurgeon implants a drain shunting the CSF to the veins of the neck or abdomen

aseptic lumbar puncture in 3rd or 4th lumbar interspace with local anesthesia

50 to 180 mm Hg

10 to 30 mm less than normal pressure

#1-Chemistry, #2-Microbiology, #3-Cell Counts

clear and colorless, viscosity like water

number of cells

increased number of cells in CSF

WBC >200 cells/mL or RBC >400 cells/mL

microorganisms or increased protein

abnormal color of CSF

A. Greatest amount of blood in tube 1, least in tube 3
B. after centrifugation, colorless supernatant

A. Consistent amt of blood in all 3 tubes
B. After centrifugation, xanthrochromic supernatant
C. macrophages with phagocytosed RBC

0-5 WBC/μL, specifically lymphocytes and monocytes

not normally present

to prevent lysing of WBCs

slowed at 4 °C

hemacytometer, undiluted specimen, counting all 9 squares on both sides

Neotrophils, lymphocytes, and plasma cells
Monocytes, eosinophils, and other cells

Bacterial meningitis (up to 90% WBC)
Early viral, fungal, TB, or parasitic infections
Some noninfectious conditions

Viral, TB, funal, ,or syphilitic meningitis (later stages)

multiple sclerosis and acute viral and chronic inflammatory conditions

antibody producing

mixed cell patterns like TB, fungal meningitis, chronic bacterial meningitis, or rupture of cerebral abscess

10% greater with parasitic, fungal, or allergic reactions

ependymal, chorooid plexus, or malignant cells in clumps

15-45 mg/dL

infants and older adults

1. contamination with blood during traumatic tap
2. change in blood-brain barrier
3. decreased reabsorption into venous blood
4. increased synthesis in CNS

bacterial/viral meningitis
cerebral infaction
hemorrhage
multiple sclerosis
obstruction of CSF flow
trauma

body is rapidly producing spinal fluid or there is a loss of fluid

assess permeability of blood-brain barrier

< 9 normal
9-14 minimal impairment
15-100 moderate to severe
> 100 complete breakdown of barrier

CSF/serum albumin index = (Albumin csf (mg/dL))/(Albumin serum (g/dL))

many conditions,
meningitis

plasma value 30-90 minutes before CSF collection

conditions impairing blood supply or transport of oxygen to CNS; viral meningitis normal, othere are elevated

multiple sclerosis and other demyelinating diseases

transthyretin, albumin, and 2 distinct transferrin bands

second band of transferrin known as 'tau protein'

to identify oligoclonal bands that are present in CSF but absent in serum in multiple sclerosis

bacteria and fungi

cryptococcus neoformans

TB and meningitis

for ameba Naegleria fowleri

to detect bacterial cause