CSF Flashcards
a major fluid of the body
Cerebrospinal fluid (CSF)
Functions of CSF
- supply nutrients to the nervous tissue
- remove metabolic wastes
- produce a mechanical barrier to cushion the brain and spinal cord against a trauma
brain and spinal cord are lined by
Meninges
meninges consist of 3 layers
Dura mater, arachnoid, pia mater
- Latin for hard mother
- outer layer that lines the skull and vertebral canal
Dura mater
spiderweb like, filamentous inner membrane
Arachnoid
gentle mother, thin membrane lining the surfaces of the brain and spinal cord
pia mater
CSF is produced in the _ of the lateral, third, and fourth ventricles
Choroid plexuses
Fluid produced every hour for adults
20 mL of fluid
the fluid flows through the - located between the arachnoid and pia mater
Subarachnoid space
volume of CSF maintained in adults
90 to 150 ML
volume of CSF maintained in neonates
10 to 60 ml
to maintain a specific volume in adults and neonates, the circulating fluid is reabsorbed back into the capillaries in the
Arachnoid granulations / villae
Are capillary networks that form the CSF from plasma by mechanisms of selective filtration
Choroid plexuses
capillary walls throughout the body are lined
with
endothelial cells
loosely connected to allow passage of soluble nutrients and wastes between the plasma and tissue
Endothelial cells of capillary walls
Have very tight fitting junctures that prevent the passage of many molecules
endothelial cells of choroid plexus
tight fitting structure of the endothelial cells in the choroid plexuses
blood brain barrier
CSF is routinely collected by
lumbar puncture
location of CSF collection
between the 3rd, 4th, or 5th lumbar vertebra
CSF specimens are collected in
three sterile tubes
Tube I
chemical and serologic test, least affected by blood or bacteria
Tube 2
usually designated for the microbiology laboratory
Tube 3
is used for HEMA/ cell count, its the least
likely to contain cells introduced by the spinal
tap procedure
how hematology tubes are maintained
refrigerated
microbiology tubes are maintained by
remain at room temp
chemistry and serology are maintained by
frozen
initial appearance of normal CSF
crystal clear
3 types of epithelial cells
ependymal calls, choroidal cells, PAM cells
used to describe CSF supernatant that is pink, orange, or yellow
Xanthochromia
most common cause of xanthochromia
RBC degradation products
grossly bloody CSF can be an indication of
Intracranial hemorrhage
Cause and indication of a hazy, turbid,milky, cloudy CSF
Meningitis
Microorganisms in CSF is an indication of
Meningitis
Protein in CSF is an indication of
- Disorders affecting blood-brain barrier
- production of IgG within the CNS
Oily appearance of CSF may be the cause of
Radiographic contrast media
Cause and indication of bloody CSF
- RBC
- hemorrhage or traumatic cap
Xanthochromic CSF because of hemoglobin is an indication of
Old hemorrhage, lysed cell from traumatic cap
Xanthocromic CSF because of bilirubin may be an indication of
RBC degradation, elevated serum bilirubin level
Xanthocromic CSF because of carotene may be an indication of
Increased serum levels
Xanthocromic CSF because of protein may be an indication of
Disorders affecting blood-brain barrier
Xanthocromic CSF because of melanin may be an indication of
Meningeal melanosarcoma
Clotted CSF because of clothing factors
Introduced by traumatic tap
Pellicle appearance in CSF because of dotting factors is an indication of
Tubercular meningitis
WBCs ( particularly granulocytes) and RBCs begin to lyse within
1 hour
40% of the leukocytes disintegrate after
2 hours
Dilution ratio for CSF
1:20 or 1:10 (if clear no need to dilute)
CSF cell count formula
Ave no. of cells counted x dilution/ no. of squares counted x volume of 1 square
Preferred centrifuge for CSF specimen
Cytocentrifuge
When one differential count is performed _should be counted, classified, and reported in terms of percentage
100 cells
High CSF WBC count of which the majority of the cells are neutrophils are indicative of
Bacterial meningitis
Major clinical significance of lymphocytes
- Normal
- viral, tubercular, fungal meningitis
- multiple sclerosis
Microscopic findings of lymphocytes
All stages of development may be found
Major clinical significance of neutrophils
- Bacterial meningitis
- early cases of vital,tubercular, and fungal meningitis
- cerebral hemorrhage
Microscopic findings of neutrophils
- Granules maybe less prominent than in blood
- cells disintegrate rapidly
Monocytes major clinical significance
- Normal
- viral, tubercular, fungal meningitis
- multiple sclerosis
Microscopic findings of monocytes
Found mixed with lymphocytes
Major clinical significance of macrophages
RBCs in spinal fluid
Microscopic findings of macrophages
May contain phagocytized RBCs appearing as
- empty vacuoles or ghost cells,
- hemosiderin granules, and
- hematoidin crystals
Blast forms major clinical significance
Acute Leukemia
Blast forms microscopic findings
Lymphoblasts, myeloblasts, or monoblasts
Major clinical significance of lymphoma calls
Disseminated lymphoma
Microscopic findings of lymphoma cells
Resemble lymphocytes with cleft nuclei
Major clinical significance plasma cells
Multiple sclerosis, lymphocyte reactions
Plasma cells microscopic findings
- Traditional and classic forms seen
- reactive lymphs
Major Clinical Significance Of Ependymal, choroidal, and spindle-shaped cells Malignant cells
Diagnostic procedures
Microscopic findings of Ependymal, choroidal,
and spindle-shaped cells
Seen in clusters with distinct nuclei and distinct cell
walls
Major clinical significance of malignant cells
Metastatic carcinomas, primary CNS carcinoma
Malignant cells microscopic findings
Seen in clusters with fusing of cell border and nuclei
