Body Fluids Flashcards
What three membranes cover the brain + spinal cord (out to in?)
Duramater
Arachnoid Mater
Pia Mater
Where is CSF found?
In the subarachnoid space, between arachnoid and pia mater
How is CSF formed? (Roughly…what cell and what kind of transport?)
formed by choroid plexus cells which turn plasma into CSF; active transport between blood + CSF (active secretion)
What are the volume ranges of CSF for Adults and neonates?
A: 90 - 150 mL
N: 10 - 60 mL
True or false: CSF is an ultrafiltrate
False, it is not an ultrafiltrate
True or false: CSF is reabsorbed into the blood in arachnoid granulations via one way valves
True
Compared to blood, what is the composition of CSF?
- Less glucose, bicarb/urea
- more Na+, Mg+ and Cl-
- very little protein
What controls substance presence in CSF?
The blood brain barrier
Are Abx (antibiotics) and medicines included in the blood brain barrier?
No they are excluded
What are some functions of the blood brain barrier?
- protecting the brain/spinal cord from traumatic pressure
- maintain chemical environment
- remove waste
What is the purpose of CSF examination?
Examine if you suspect infections/hemorrhage/tumor and can treat intracranial hypertension
What is the process of CSF collection called?
Lumbar puncture, between L3-L4 vertebrae
True or false: CSF collection usually has passive dripping, higher pressures mean faster outputs of CSF.
True
how early should you perform a cell count/slide after collection of CSF?
30 minutes of receipt
True or false: for CSF, you can perform cell counts with tubes for chemistry and hematology
True
True or false: You can only perform a diff on a CSF sample tube for hematology
True, it has the most accurate counts since it is the least contaminated
If not possible to test immediately after CSF collection, how would you store:
Hem tubes?
Chem/serology?
Micro?
Extra fluids?
Hem - refrigerate
Chem - frozen
Micro - RT
Extras - frozen
What do the progression of tubes look like in a Traumatic Tap?
Subsequent tubes become more clear although some blood is present
What do the progression of tubes look like in a Hemorrhage?
all tubes are equally bloody :( ew
Xanthochromic coloring is seen in which CSF sample tap? (traumatic or hemorrhage?)
Hemorrhage, it is caused by bilirubin
True or false: Traumatic Tap does not have a clot
False: traumatic taps have clots; hemorrhages do not since the clot already happened
What is erythrophagia? what does it relate to?
Red cells being eaten by macrophages (long live) it is related to hemorrhages
True or false: Hemorrhages are positive for D-Dimers
True
Explain the difference in appearance of low turbidity and high turbidity in CSF
Low turbidity is clear
high turbidity is colored (color is reported by chemistry)
What is the reference range of protein in CSF (chemistry)?
15 - 45 mg/dL
What is the equation for corrected CSF protein?
Correct CSF = Measured CSF protein - CSF RBC/1200
(every 1200 rbc increases the protein)
Causes of CSF protein is >65 ?
Damage to blood brain barrier (meningitis/hemorrhage)
Ig production
decreased clearance
degeneration of tissues
What causes a decrease in CSF protein?
leakage
Low levels of Glucose in CSF is caused by what? high levels?
low - meningitis or subarachnoid hemorrhage
High levels - traumatic tap, diabetic coma
True or false: Myelin basic protein is used to monitor MS
True
What does IEF do?
Detects bands (Igs) and indicates if there is inflammation (oligoclonal)
What do you use to dilute a sample with many cells in a CSF collection?
Dilute w/ saline
In a CSF sample with many cells, what solution would you use to lyse RBCs? what is it composed of?
Turk solution, made of glacial acetic acid or methylene blue
How many primary squares are counted for CSF cell counts?
9 primary squares (count entire chamber unless count is very high)
What is the WBC reference range for CSF cell counts?
WBC (all less than or equal to)
Adults <5 / mm3
Child <10 / mm3
Neonate <30 /mm3
What is the RBC ref range for CSF cell counts?
less than or equal to RBC <5 /mm3
True or false: Traumatic tap does not affect cell counts
False, it does affect the count
What is the equation for corrected CSF WBC?
Corrected = Measured CSF wbc - blood wbc * CSF rbc/blood rbc
What must you do to a CSF sample before performing a WBC Diff?
Cytocentrifuge it so that it concentrates it into a monolayer
What can you add to a CSF sample to increase the cell yield and stabilize the membrane during a WBC diff?
Albumin (30%) but can also produce some cellular distortion
What are the ref ranges for cells in a WBC diff for CSF?
Adults approx 70% lymphs
30% monos
occasional PMN ok
Neonates
30% lymphs
70% monos
What cell is primary in Bacterial Meningitis?
Neuts (duh) and they often contain phagocytized bacteria
What cells are increased in viral/fungal TB and meningitis? HIV/AIDS?
Lymphs and monos
Reactive lymphs with viral meningitis
MS has 50 or less lymphs
Also seen with HIV/AIDS
True or false: Macrophages may be seen after many taps (CSF)
TRUE
What cells are seen with Bone marrow contamination?
nRBCs
True or false: macrophages enter CSF during a hemorrhage within 2hr to phagocytize rbcs
yes true
What are hemosiderin granules?
Dark granules caused by degraded RBCs (macros phagocytized them)
True or false: Choroidal cells are epithelial lining cells of choroid plexus and can be singular or clumped
true
What cells would you see in a smear of someone with Leukemia?
Lymphoblasts, monoblasts and myeloblasts
