CM Exam 4: Body Fluid Analysis

the liquid that occupies spaces of

the central nervous system (CNS)

CSF

CSF specimens are collected by what

lumbar puncture

Where are lumbar punctures performed?

L3 and L4 or L4 and L5

how many tubes used for CSF specimen

4

what CSF tube:

protein and glucose level (chemistry analytes)

1

what CSF tube:

gram stain, meningitis PCR panel, cultures

2

what CSF tube:

cell count and differential

3

what CSF tube:

when indicated, VDRL test or india ink stain

4

what does blood in first two CSF tubes but not all 4

traumatic tap

what does blood in all 4 CSF tubes indicate

brain bleed

normal or abnormal CSF:

- Colorless

- Clear

- Free of clots and blood

normal

normal or abnormal CSF, what appearance:

- Increased numbers of RBCs and/or WBCs

- High protein levels

- Microorganisms

abnormal

cloudy

normal or abnormal CSF, what appearance:

- Increased number of RBCs

abnormal

reddish (hazy-color)

If ALL the sample tubes have an “even”

amount of reddish color =

cerebral hemorrhage likely

CSF: If the reddish color is most intense in the first tube then is absent by the 3rd or 4th =

traumatic tap

normal or abnormal CSF, what appearance:

- Hemoglobin from lysed RBCs (blood has been in the CSF

for at least 1-2 hours)

- Bilirubin: from degraded hemoglobin or from

hyperbilirubinemia

- Elevated protein level exceeding 150 mg/dL

abnormal

xanthochromic (orange or yellow color)

what WBC would you see increased for:

bacterial meningitis and cerebral hemorrhage

neutrophils

what WBC would you see increased for:

fungal, TB, and aseptic (viral) meningitis, and multiple sclerosis

lymphocytes

what WBC would you see increased for:

leukemias, lymphomas, metastatic

tumors

malignant cells

Gram-negative diplococci consistent with Neisseria species. This patient probably has

_____ _____ caused by Neisseria meningitidis

meningococcal meningitis

bacteria that have been phagocytized by WBC

intracellular bacteria

With viral meningitis - _____ are predominant type of WBC seen in the CSF in adults

lymphocytes

With viral meningitis - _____ are predominant type of WBC seen in the CSF in children

monocytes

due to a viral infection, there are usually ____ _____

reactive lymphocytes (making Igs)

increased number of plasma cells contribute to ____ production

Ig

when are plasma cells seen in CSF

multiple sclerosis

Specialized system of capillary endothelial cells that protects

the brain from harmful substances in the blood stream

blood brain barrier

oftentimes this is the rate-limiting factor in determining whether a therapeutic drug enters CSF

blood brain barrier

can you have protein in CSF and everything be fine?

yes but very little

normal range for CSF total protein

15-45

What can lead to increased CSF total protein (3)

- blood from traumatic tap

- damage to BBB

- increased CNS protein synthesis

most common reason for decreased CSF total protein

fluid leaking from CSF

An increase in the ratio of CSF albumin to serum albumin is

indicative of an ______

impairment of BBB

normal albumin CSF index

<9

CSF albumin index:

value of 9-14 indicates

minimal impairment

CSF albumin index:

value of 15-100 indicates

moderate to severe impairment

CSF albumin index:

value of > 100 indicates

complete breakdown of BBB

Increased amounts of ____ can result from increased transport

from plasma or from IgG production by CNS tissues (as in

multiple sclerosis)

IgG

MS is an autoimmune disease that causes damage to _____

myelin

A CSF myelin basic protein (MBP) level provides an index of active _____

demyelination

MBP levels are increased OR decrease in diseases that cause demyelination

increased

what do we use to separate CSF proteins

elecrophoresis

What would show up in an abnormal CSF elecrophoresis

dark oligoclonal bands

looking at a CSF electrophoresis, you see these dark bands in the CSF which indicates ____

oligoclonal bands

MS

hyperglycemia causes an elevation in CSF _____

glucose

bacterial or viral meningitis shows decreased glucose level

bacterial

does viral meningitis eat glucose

no

this is found in meningitis caused by bacteria, fungi, or mycobacteria

lactate elevation

what microbiology test is useful in detecting mycobacterial meningitis

acid-fast stain

useful in detecting fungal meningitis

caused by Cryptococcus neoformans

india ink preparation

both ____ and ____ are preformed in cases of meningitis

CSF

blood cultures

CSF meningitis panel is performed using what

PCR

associated with the diagnosis of tertiary syphilis (neurosyphilis)

- detects antibodies in the CSF

VDRL (venereal disease research lab)

meningitis --

glucose: decreased

lactate: elevated

gram stain: bacterial

bacterial meningitis

meningitis --

glucose: decreased

lactate: elevated

gram stain: fungal

fungal

the india ink prep is positive if this is present

cryptococcus fungal meningitis

meningitis --

glucose: decreased

lactate: elevated

acid-fast stain: 20-40% change its positive

mycobacterial meningitis

meningitis --

glucose: normal

lactate: normal

PCR: positive possibly

Viral culture performed

aseptic (viral) meningitis

meningitis --

glucose: normal

lactate: elevated

specific disease sxs will be present for this patient

MS

Viscous fluid found in joint cavities which is formed as an

ultrafiltrate of plasma across the synovial membrane

synovial fluid (joint fluid)

collection of synovial fluid by needle aspiration

Arthrocentesis

normal or abnormal synovial fluid:

clear, colorless to straw, does not clot

normal

synovial fluid appearance indications:

dark yellow

inflammation

synovial fluid appearance indications:

green/greenish-yellow

bacterial infection

synovial fluid appearance indications

cloudy

elevated # of cells, organisms, crystals

synovial fluid appearance indications

red

elevated # of RBC (traumatic injury, hemorrhagic)

do you want (+) or (-) string test

positive (synovial fluid should be viscous)

tihs test is abnormal in rheumatoid arthritis, septic arthritis, and other inflammatory joint diseases

mucin clot test

normal or abnormal mucin clot test:

A firm white clot of mucin in a clear solution

normal

normal or abnormal mucin clot test:

the mucin clot is a flocculent precipitate in a cloudy solution

abnormal

whats an abnormal cell count for synovial fluid

increased WBC and/or RBC

looking at uric acid and see:

crystals more horizontal are blue, while crystals that are

more vertical are yellow

needle shaped

gout

looking at uric acid and see:

crystals more horizontal are yellow, while crystals that are

more vertical are blue

rhomboid shaped

Pseudogout (like gout. but crystals are calcium pyrophosphate not uric acid

a decreased synovial fluid glucose is indicative of

inflammatory and septic disorders (due to WBC and bacteria eating glucose)

Fluid found in membranous sac that surrounds the fetus

amniotic fluid

collection of fluid by needle aspiration from the amniotic sac

amniocentesis

will detect chromosomal

abnormalities like down syndrome, and provide the sex of fetus

cytogenic evaluation

Amniotic fluid exam:

Alpha-fetoprotein level can be

measured to detect possible

_____ defects

neural tube

Amniotic fluid exam:

Evaluation of the ______ level is used to detect abnormal

fetal RBC hemolysis due to Hemolytic Disease of the

Newborn (HDN)

bilrubin

Measurement of fetal alveolar surfactant is used to

evaluate _____

fetal lung maturity

______ is required to prevent fetal lung

atelectasis (alveolar collapse)

Sufficient surfactant

The two surfactants routinely measured in the laboratory are

_____ and ______

lecithin

PG (phosphatidylglycerol)

by doing the lecithin-sphingomyelin (L/S) ratio - you can test for what fetal development

lung development (positive lecithin in amniotic fluid usually means lungs are developed)

With L/S ratio:

if ratio remains low and constant it indicates what?

lungs not developing, preterm delivery not safe

With L/S ratio:

preterm delivery is considered relatively safe when the L/S ratio reaches what?

2.0

The parietal membrane lines the ____

cavity wall

The visceral membrane covers the ____

organs

______ is an ultra-filtrate of serum and provides

lubrication between the two membranes

Serous fluid

Serous fluid collected by needle aspiration from what cavity:

thoracentesis

pleural cavity (lungs)

Serous fluid collected by needle aspiration from what cavity:

pericardiocentesis

pericardial cavity (heart)

Serous fluid collected by needle aspiration from what cavity:

paracentesis

peritoneal cavity (abdomen tap)

normal serous fluid appearance

clear and pale yellow

an effusion that forms because of a systemic disorder that disrupts the balance in the regulation of fluid filtration and reabsorption (fluid overload problem)

transudate

transudate or exudate? what is the dx?:

massive serous fluid accumulation

within the peritoneal cavity due to cirrhosis of the liver

transudate

ascites

an effusion that forms because of disorders that directly involve the membrane of the cavity that increase capillary permeability

exudate

transudate or exudate?:

bacterial pneumonia, malignancies

exudate

serum acites albumin gradient (SAAG):

SAAG > 1.1 indicates _____

SAAG < 1.1 indicates ______

transudate

exudate

Glucose T vs E:

equal to serum level

< or equal to serum level

transudate

exudate

Fluid to serum protein ration T vs E:

> 0.5

< 0.5

exudate

transudate

ODes transudate or exudates have lactate dehydrogenase < 60% of serum

transudates