CEREBROSPINAL FLUID Flashcards
1st recognized by
Cotugno (1764)
3rd MAJOR FLUID IN THE BODY
CSF
produced in the [?] and serves several functions
brain
serves as a protective fluid, cushioning and lubricating the brain and spinal column.
CSF
The brain and spinal cord are enclosed in three layers of membrane, the meninges:
DURA MATER
ARACHNOID MATER/ARACHOIDEA
PIA MATER
”hard mother”- Outermost membrane
DURA MATER
”spider-web-like”- Middle
ARACHNOID MATER/ARACHOIDEA
”gentle mother”- Innermost layer and adheres to the surface of neural tissue.
PIA MATER
Produced by
CHOROID PLEXUSES
flows through
SUBARACHNOID SPACE
reabsorbed by
ARACHNOID VILLI/GRANULATION
VOLUME:
20mL/hour
Adults: 140-170ml
Neonates: 10-60ml
used to represent the control and filtration of blood components to the CSF and to the brain
BLOOD-BRAIN BARRIER(BBB)
SPECIMEN COLLECTION AND HANDLING SITES
ADULTS:
Between 3rd and 4th (or lower) lumbar vertebrae
SPECIMEN COLLECTION AND HANDLING SITES
CHILDREN:
Between 4th and 5th lumbar verebrae
most common position
LUMBAR PUNCTURE (fetal position/Lateral Decubitus Position)
: sub-occipital region
Cisternal Puncture
: infants with open fontanels
Ventricular Puncture
collection positions
LUMBAR PUNCTURE (fetal position/Lateral Decubitus Position)
Cisternal Puncture
Ventricular Puncture
Lateral cervical puncture
Chemical & serological tests
1
Frozen at -15 to -30oC
1
Microbiological tests
2
Room Temp at 19 to 26 oC
2
Cell count /Hematology
3
Refrigerated at 2 to 8 oC
3
Microbiology /chemistry/serology
4
LOW-VOLUME Specimens –
Microbiology > Hematology > Chemistry/Serology
STAT basis (WITHIN [?])
30 MINUTES
—most frequently performed chemical test on CSF
Protein
Protein Normal values:
6 months to adults =
Newborn =
> 60 y/o =
15 to 45 mg/dl
75 to 150 mg/dl
>60 mg/dl
ALBUMIN > PREALBUMIN > HAPTOGLOBIN AND CERULOPLASMIN > TRANSFERRIN
DECREASED IN PROTEINS
Leakage fluid in CNS
Recent puncture
Water intoxication
Rapid CSF production
QUALITATIVE TESTS
NONNE-APELT
ROSE JONES
PANDY’S
NOGOCHI
NONNE-APELT
Reagent:
Product:
Ammonium sulfate
Cloudy precipitate
ROSE JONES
Reagent:
Product:
Ammonium sulfate
White ring
PANDY’S
Reagent:
Product:
Phenol
Bluish white cloud
NOGOCHI
Reagent:
Product:
10% Butyric acid
Precipitate
QUANITATIVE TESTS
- TURBIDIMETRIC
- DYE-BINDING TECHNIQUES
- NEPHELOMETRY
- ELECTROPHORESIS
- TURBIDIMETRIC REAGENTS
TRICHLOROACETIC ACID(TCA)
SULFOSALICYLIC ACID(SSA)
- DYE-BINDING TECHNIQUES REAGENTS
COOMASSIE BRILLIANT BLUE(CBB) G250
PONCEAU S
- NEPHELOMETRY REAGENTS
Benzalkonium chloride
- ELECTROPHORESIS
“Protein Error of indicators”
DYE-BINDING TECHNIQUES
Most frequently performed
ELECTROPHORESIS
Method of choice for the determination of CSF
ELECTROPHORESIS
Detection of OLIGOCLONAL BANDS
ELECTROPHORESIS
MULTIPLE SCLEROSIS
ELECTROPHORESIS
Encephalitis, neurosyphilis, Guillain-Barre Syndrome and Neoplastic Disorders
ELECTROPHORESIS
:
- comparison between serum and CSF levels of albumin and IgG must be made
PROTEIN FRACTIONS
Evaluates BBB integrity
CSF-Serum Albumin Index
Determines IgG production within the CNS
CSF-Serum IgG Index
CSF-Serum Albumin Index Index Value
< 9: intact BBB
>9: damaged BBB
CSF-Serum IgG Index Value
> 0.77: IgG production within the CNS
Cerebrospinal Fluid Glucose
NORMAL VALUE:
Neonates:
60-70%
80%
Cerebrospinal Fluid Glucose INCREASED IN:
Plasma glucose elevation
DM
Encephalitis and conditions associated with intracranial pressure
Cerebrospinal Fluid Glucose DECREASED IN:
Aids in determining the causative agent of
meningitis
GLUCOSE CONCENTRATION IN BACTERIAL
DECREASED
GLUCOSE CONCENTRATION IN TUBERCULAR
DECREASED
GLUCOSE CONCENTRATION IN VIRAL
NORMAL
GLUCOSE CONCENTRATION IN FUNGAL
NORMAL OR DECREASED
INCREASED NEUTROPHILS
BACTERIAL
INCREASED LYMPHOCYTES
TUBERCULAR AND VIRAL
+ INDIA INK(C.neoformans)
FUNGAL
Aids in the diagnosis and management of meningitis
Cerebrospinal Fluid Lactate
Used to evaluate effectiveness of antibiotic therapy
Used to monitor severe head injuries
Cerebrospinal Fluid Lactate
< 25 mg/dL:
VIRAL MENINGITIS
> 25 mg/dL:
TUBERCULAR AND FUNGAL MENINGITIS
> 35mg/dL:
BACTERIAL MENINGITIS
Cerebrospinal Fluid Glutamine
NORMAL VALUE:
8-18mg/dL
Frequently performed in CSF but not in blood
Cerebrospinal Fluid Glutamine
INDIRECT measure of CSF AMMONIA
Cerebrospinal Fluid Glutamine
Aids in the diagnosis of meningitis
Cerebrospinal Fluid LD Isoenzymes
LD1 and LD2 :
brain tissue destruction
LD2 and LD3 :
viral meningitis
LD4 and LD5 :
bacterial meningitis
CK-BB
>17mg/dL
<17mg/dL
WBC: COUNT:
routinely perfomed
RBC COUNT:
traumatic tap and correction for leukocytes or proteins
RBC count=
Total Cell count-WBC count
TOTAL CELL COUNT:
hemocytometer
Diluent:
Normal saline solution(NSS)
Disturbance in consciousness (>35mg/dl)
Glutamine
Coma of unknown origin (results from ↑ usage of α-ketoglutarate)
Glutamine
Reye’s syndrome (75% of diagnosed children)
Glutamine
in post-cardiac arrest indicates poor prognosis
CK-BB Isoenzyme >17mg/dL
indicates recovery from cardiac arrest after resuscitation
CK-BB Isoenzyme <17mg/dL
predominant in adults
Lymphocytes
lymphocyte to monocyte ratio
70:30
predominant in children
monocytes
lymphocyte to monocyte ratio
30:70
: rare normal cell component
neutrophils
: ↑numbers of normal cells (abnormal finding)
Pleocytosis
Abnormal CSF Cells:
immature WBCs, eosinophils, plasma cells, macrophages, increased tissue cells and malignant cells
Performed when there is: (1) traumatic tap, (2) a need for leukocyte correction, and (3) a need for protein correction
RBC Count
𝑹𝑩𝑪 𝑪𝒐𝒖𝒏𝒕 =
𝑹𝑩𝑪 𝑪𝒐𝒖𝒏𝒕 = 𝑻𝒐𝒕𝒂𝒍 𝑪𝒆𝒍𝒍 𝑪𝒐𝒖𝒏𝒕 − 𝑾𝑩𝑪 𝑪𝒐𝒖𝒏𝒕
Total Cell Count
Cells are counted in the four corner squares and the center square of the [?]
[?] is used to load the hemocytometer
Diluent: [?]
Improved Neubauer hemocytometer
Pasteur pipet
Normal Saline Solution (NSS)
𝑪𝒆𝒍𝒍𝒔/𝒖𝑳 =
Dilution
20
Sample is undiluted and examined using a phase-contrast microscope
Fuchs-Rosenthal Counting Chamber
With 16 large squares and 0.2 mm depth
Fuchs-Rosenthal Counting Chamber
Fuchs-Rosenthal Counting Chamber Cells Formula
Number of cells/3
Specimens are concentrated and stained
Differential Count
Number of cells counted: 100
<100 cells: report # of cells counted
Differential Count
Performed to identify the causative agent in meningitis
MICROBIOLOGIC EXAMINATION
MICROBIOLOGIC EXAMINATION SPECIMEN:
CSF and blood
MICROBIOLOGIC EXAMINATION
Specimens should be concentrated by centrifugation at
1500xg for 15 minutes
Microorganism must be recovered from CSF by growing it on appropriate culture medium for positive identification
Blood Culture
Medium for culture
Thioglycholate broth and Chocolate agar
Blood Culture Duration of incubation:
bacterial meningitis
tubercular meningitis
24 hours
6 weeks
Confirmatory procedure rather than diagnostic
Blood Culture
Cultures are to what percentage sensitive
80% to 90%
Gram Staining is to what percentage sensitive
60% to 90%
Microorganism must be recoverd from CSF by growing appropriate [?] for identification
culture medium
Routinely performed on CSF from all suspected cases of meningitis
Gram Staining
Recommended method for the detection of organisms
Gram Staining
of organism should be present for adequate Gram stain results
100,000/ml
Organisms most frequently observed:
Gram (+):
Gram (-):
Star burst pattern:
Streptococcus pneumoniae (cocci) Streptococcus agalactiae (cocci) in newborns Listeria monocytogenes (bacilli) in newborns
Escherichia coli (bacilli) Neisseria meningitides (cocci) Haemophilus influenza (pleomorphic bacilli)
Cryptococcus neoformans
Performed when tubercular meningitis is suspected
Acid Fast/Fluorescent Antibody Stains
Positive report is extremely valuable
Acid Fast/Fluorescent Antibody Stains
Detect the presence of a thickly encapsulated Cryptococcus neoformans
India Ink
More sensitive method in the detection Cryptococcus neoformans in serum and CSF
Reverse Latex Agglutination
Should be confirmed by culture and India ink
Reverse Latex Agglutination
False positive reactions occur mainly due to rheumatoid factor
Reverse Latex Agglutination
Used in combination with hematology and clinical chemistry results
Bacterial Antigen Test
Provide rapid means for detecting and identifying microorganisms in CSF
Latex Agglutination Tests and ELISA
Test kits available for the detection of Streptococcus group B, Haemophilus influenzae type B, Streptococcus pneumoniae, Neisseria meningitidis A, B, C, Y, W135, and Escherichia coli K1 antigens.
Latex Agglutination Tests and ELISA
Diagnosis of meningitis caused by Gram (-) organisms
Limulus Lysate Test
Principle: The endotoxin produced by the cell walls of Gram (-) organisms will coagulate the amebocyte lysate within 1 hour incubated at 37oC.
Limulus Lysate Test
Reagent: Blood cells (amebocyte) of horseshoe crabs (Limulus polyphemus)
blue in color due to the presence of a copper complex
Limulus Lysate Test
Performed for the diagnosis of neurosyphilis
Venereal Disease Research Laboratories (VDRL)
Most sensitive and specific for syphilis diagnosis
Fluorescent Treponemal AntibodyAbsorption (FTA-ABS)
Confirmatory test for meningitis
Culture
Causative agent of primary meningoencephalitis
Naegleria fowleri
Seen in wet preparations
Motile trophozoite
Cytocentrifuged
Non-motile trophozoite
Specimens accompanied by increased wbc but no bacteria
Non-motile trophozoite
Crystal clear
Normal
Hazy, turbid, milky, cloudy
WBCs Microorganisms Protein
Oily
Radiographic contrast media
Bloody
RBCs
Xanthochromic
Hemoglobin Bilirubin Carotene Protein Melanin
Clotted
Protein Clotting factors
Pellicle
Protein Clotting factors
