LAB EXAM 2: Body Fluids Flashcards
What are the three major types of body fluids?
CSF (cerebrospinal, NOT cerebral spinal)
Synovial
Serous
The epithelial cell exterior of
choroid plexus is the…
“blood-brain barrier”
Produced constantly in brain choroid plexi (“plexuses”, capillary knots that protrude into brain ventricles).
Cerebrospinal Fluid (CSF)
Cerebrospinal Fluid (CSF) is formed via both __________ and ___________ processes.
filtration, active transport
CSF flows over and around….
brain and spinal cord
What is the total CSF volume in adults?
90-150 mL
CSF is produced at a rate of about _____mL/24 hours.
500
What are the three major CSF functions?
Supply nutrients
Remove waste
Act as mechanical barrier & cushion for brain & spinal cord
True or false:
All CSF tubes should be treated as highly infectious
True!!!
“lumbar puncture” is used to collect CSF fluid.
Between what lumbar vertebrae is the puncture done?
between 3rd & 4th, or
4th & 5th, lumbar vertebrae.
CSF Specimen Collection:
Most hospitals usually collect _____ sterile tubes &
label them in the order withdrawn.
3
CSF Specimen Collection:
What is tube #1 used for?***
Chemistry & Serology (1st fluid withdrawn; contains skin plug, but this will get centrifuged & removed.)
C/S
CSF Specimen Collection:
What is tube #2 used for?***
for Micro. (middle of fluid withdrawal; less likely to have skin flora contaminants.)
M
CSF Specimen Collection:
What is tube #3 used for?***
Hematology (last of fluid withdrawn; least likely to have skin cell contamination.)
H
How quickly must CSF samples be processed?
Within 1 hour (STAT)
If there is a 4th tube of CSF, what is it used for?
Gets frozen for extra testing that may be needed later on.
How should Heme tubes be stored if not tested STAT?
refrigerate
CSF cell counts MUST be done within ______ hour.
one, (One hr. is usual t.a.t. for fluid cell counts,
anyway.)
What temp should micro tubes be at for CSF?
room temp. and set up ASAP
_______ CSF tubes may be frozen after centrifugation.
Chem./Sero.
Why should you never discard leftover CSF fluid?
in case more tests are ordered!
What is the normal appearance of CSF?
“crystal clear & colorless”
(appearance must be described in report).
What does Xanthochromic mean?
ANY color of supernate
left AFTER centrifugation.
What can be done to determine CSF supernatant color?
To see colors clearly, centrifuge a Hct capillary or other clear tube filled with CSF, then hold supernate up against a white background.
What could cause cloudy, milky, or turbid CSF?
May be due to ↑ protein,
lipids, or WBCs!
What is the cause of clear pink or red Xanthochromia?
oxyHgb due to blood degradation (> 2
hrs. but < 2 d.)
(The “2X2 rule”.)
What is the cause of orange xanthochromia?
Heavy hemolysis (> 2 hrs. but < 2 d.), or
Carotenemia
What is the cause of yellow Xanthochromia?
OxyHgb broken down to unconjugated bili. from:
Heavy, long-term (> 2 days) hemolysis, or
Kernicterus
What are the two possible causes of bloody or hemolyzed CSF specimens?
Traumatic tap
- inadvertent blood vessel trauma from puncture.
Intracerebral or subarachnoid
hemorrhage (ICH or SAH)
- Must be differentiated from traumatic tap!
What can cause oily CSF samples?
radiographic contrast media
Blood evenly distributed throughout collection tubes.
Traumatic Tap or Intracerebral Hemorrhage?
Intracerebral Hemorrhage***
Siderophages are highly indicative of?
Intracerebral Hemorrhage***
Traumatic Tap or Intracerebral Hemorrhage?
Clear supernatant if recent, but: Xanthochromic supernatant if old! (Good clue but not specific!)
Intracerebral Hemorrhage
In tubercular meningitis, overnight CSF refrigeration may cause a “weblike pellicle” (scum) to form. This should NOT be confused with __________.
clotting
Traumatic Tap or Intracerebral Hemorrhage?
Serum protein contamination may cause xanthochromic supernatant.
Traumatic Tap
Traumatic Tap or Intracerebral Hemorrhage?
Uneven distribution of blood in collection tubes (heaviest in 1st, less in 2nd, etc.)
Traumatic Tap
Traumatic Tap or Intracerebral Hemorrhage?
Sample often (but not always!) clotted (due to plasma fibrinogen
contamination); may even have bloody streaks.
Traumatic Tap
Traumatic Tap or Intracerebral Hemorrhage?
No blood clots
Intracerebral Hemorrhage
What are the causes of protein in CSF?
-Disorders of blood-brain barrier: Ex.:
↑ IgG within CNS = MS
↑ Bld. - brain barrier permeability =
Guillain-Barre syndrome (rarer)
-Old hemorrhage, lysed cells from traumatic tap
-Traumatic tap
N. adult CSF = _____ WBCs/uL & ___ RBCs/uL.
0-5, 0
Why must numerical CSF counts be performed immediately?
danger of cell lysis! (40% of WBCs can disintegrate within 1st 2 hrs. following collection!)
Typical time limit for CSF analysis is within ____ hour.
1
What stain is used for CSF differential cell counts?
Wright-stained slide prepared from
cytocentrifuge prep
What is the principle of Differential Cell Counts on CSF?
under slow centrifugal force, body fluid is driven through a cuvette outlet, such that cells are deposited as a monolayer button on slide, &
excess fluid is absorbed by a filter card.
What are 2 advantages of Wright-stained slide prepared from
cytocentrifuge prep?
Minimizes cell distortion
Concentrates cells for counting
What should be done if CSF cell counts are low?
use hemacytometer for
count, & report only #s of cell types seen.
CSF cell counts:
Count _____ cells, classify & report as percentages
100
What prep can be done to cushion cells for CSF counts?
7% albumin can
be added before cytocentrifugation. Take 22% BB albumin & dilute, then add 1 drop 7% albumin to 5
drops of specimen. This only works for CSF & serous
fluids, NOT for synovial fluids!
CSF Cell counts:
What cells are normal to be seen?
-few lymphs and monos
-very rare segs IF it is a concentrated specimen
CSF counts:
-N. adult CSF, majority WBCs = __________
-N. pedi. CSF, majority WBCs = __________
lymphs
monos
Pleocytosis =
↑ #s of otherwise N. cells; an
abnormal finding!
Ex. lymphocytosis or
monocytosis
What is the major clinical significance of lymphocytes in CSF?
-N. in small numbers
-Lymphocytosis = viral,
tubercular, fungal meningitides
-Multiple sclerosis (but with
leukopenia of < 25/uL, & only
lymphs!) (can be plasma cells in this case)
What is the major clinical significance of neutrophils in CSF?
N. if very rare (conc. specimens)
Neutrophilia = bacterial
meningitis or early cases viral, tubercular or fungal meningitis Cerebral hemorrhage
What is the microscopic finding seen with neutrophils in CSF?
Granules may be less
prominent than in p.b.
What is the microscopic finding of neutrophilia with cerebral hemorrhage?
Cells disintegrate rapidly
What is the major clinical significance of monocytes in CSF?
N. in small numbers. Monocytosis = chronic bacterial meningitis, viral,
tubercular, & fungal meningitis, MS
-Found mixed with lymphs
What is the clinical significance of eosinophils seen in CSF?
-Parasitic infections (Ex., Taenia solium)
-Allergic reactions
-Intracranial shunts
What is the clinical significance of plasma cells seen in CSF?
Multiple sclerosis (MS)*
What is the clinical significance of macrophages seen in CSF?
Viral & bacterial meningitides.
Also, any RBCs in CSF from
long-term cause
What are the microscopic findings with macrophages in CSF?
Erythrophages;
siderophages in ICH
What is the clinical significance of blasts seen in CSF?
Acute leukemia
Microscopic Findings: Lympho- or myeloblasts
What is the clinical significance of malignant cells in CSF?
Metastatic carcinoma /
leukemia***
What are the microscopic findings with malignant cells?
Very large; 3-D clusters
with fusing of cell borders, aberrant polyploid nuclei,
cytoplasmic blebbing***
What are the microscopic findings with Ependymal &/or Choroidal cells?
Normal trauma, diagnostic
procedures***
What are the microscopic findings with Ependymal &/or Choroidal cells?
Flattened 2-D sheets,
clustered, with distinct
nuclei & cell membranes***
What are the microscopic findings with budding yeast seen in CSF?
Cryptococcus neoformans has clear capsule surrounding it on India ink prep.
What is the clinical significance of nRBCs in CSF?
Bone marrow contamination
from tap
-NOT clinically significant!
Neutrophilia in CSF (WBCT in 1000s), think first of ?
Bacterial meningitis
Blast forms in CSF, think first of ?
Acute leukemia (secondarily, metastatic solid cancer)
Lymphocytes in CSF (WBCT in 100s), think first of:
Viral meningitis; 2nd = TB meningitis; 3rd = fungal meningitis
Plasma cells in CSF, think first of ?
MS (Multiple Sclerosis)
Eos in CSF, think what 3 conditions ?
CNS involvement of parasites; 2nd = overwhelming allergic
reactions; 3rd = intracranial shunts.
Normal body cavity lining cell characteristics…
All lie in 1 plane
Hang together as a “sheet“
Have distinct cytoplasmic & nuclear margins (“fried
egg” appearance)
May have vacuoles
***Malignant cell characteristics…
3-D clumps
Indistinct nuclear & cytoplasmic margins
Bizarre, polyploid nuclei
↑ mitotic forms
Large nucleoli
Blebbed cytoplasmic edges
body cavity lining cells are called __________ cells in all body fluids except in
CSF!
mesothelial
-Supplies nutrients to cartilage
Acts as lubricant
Synovial Fluid
Produced by filtration of plasma across the
synovial membrane, combined with secretion of
a hyaluronate-lubricin complex from same
membrane. (Hyaluronate is just the salt form of hyaluronic
acid.)
Synovial Fluid
Synovial fluid has the same chemical composition as __________.
plasma
How are synovial fluid specimens obtained?
arthrocentesis
What are the four Major Categories of Joint Diseases?
-Noninflammatory
-Inflammatory
-septic
-hemorrhagic
Example of non inflammatory joint disease?
Degenerative joint disorders
(Ex., osteoarthritis)*
-* Even though there is inflammation, it is 2o to degradation, not the 1o cause of the joint disorder!
What can cause inflammatory joint disease?
Immunologic or crystal
problems (Ex., RA & SLE,
gout & pseudogout)
What can cause hemorrhagic joint disease?
Traumatic injury, coagulation
deficiencies
What is the normal appearance of synovial fluid?
Appears clear & pale yellow
“Egg white” consistency (forms continuous
“string” when poured!)
Viscosity is due to polymerization of hyaluronic acid (essential for proper joint lubrication.)
Why would synovial fluid viscosity be measured?
Unhealthy joints secrete malfunctioning
hyaluronic acid (unable to polymerize), so viscosity ↓
Synovial Fluid:
____________ may be mixed in with fluid 1st in order to aid in handling. Also, coverslip can be rimmed with clear nail polish to prevent dehydration during
examination.
Hyaluronidase
Synovial Fluid:
Normal WBC count = _____ mononuclear cells/uL
(lymphs, monos, macrophages, & a few synovial lining cells)
< 200
FYI: WBCT count may reach > 100,000 cells/uL in severe infection!
Synovial fluid:
Segs should make up <___% of N. differential.
30
Why would a microscopic exam be done for crystals in synovial fluid?
to diagnose crystal-induced arthritis.
What are the three most common crystals causing arthritis?***
Monosodium urate (MSU) (gout)
Ca pyrophosphate (CPPD) (= pseudogout)
Cholesterol (chronic effusions such as RA)
Synovial crystal:
Large, needle-shaped crystals that may be inside OR outside cells.
Monosodium urate (MSU) (gout)
Synovial crystal:
Small rhombic-shaped or rod-shaped crystals, inside cells.
Ca pyrophosphate (CPPD) (= pseudogout)
Synovial crystal:
Large, flat, extracellular notched plates
Cholesterol (chronic effusions such as RA)
