The document provides information on cerebrospinal fluid (CSF) analysis, including its production, circulation, and examination. It discusses normal CSF values and abnormalities seen in various conditions. The lumbar puncture procedure and complications are also outlined. Abnormalities in CSF parameters like increased white blood cells, decreased glucose, and elevated proteins can indicate infections like bacterial meningitis, while more subtle changes may be seen in viral meningitis and tuberculosis meningitis. CSF analysis is useful for diagnosis.

1. CEREBRO SPINAL FLUID
ANALYSIS
Dr Anvesh Narimeti
Unit 1

2. HISTORY
 The technique for needle lumbar puncture was introduced
by the German physician Heinrich Quincke
• He was perhaps the first to
recognise angioedema whic
h is often referred to as
"Quincke's edema
"Quincke's pulse“ in AR

3. CSF PRODUCTION AND CIRCULATION

4. 1. Normal blood brain barrier is important for the normal chemistry
results of CSF
2. Mechanism of formation:
1. Selective ultrafiltration of plasma
2. Active secretion by epithelial membrane
PRESSURE OF CSF DEPENDS ON DRAINAGE SYSTEM
TOTAL PRODUCTION OF CSF PER DAY=500-600 ml per day
TOTAL VOLUME OF CSF IN ADULT IS = 140 ml
THE RATE OF ABSORPTION CORRELATES WITH THE CSF
PRESSURE

5. LUMBAR PUNCTURE
lumbar puncture should be carried out if some specific piece of
information is likely to come from csf examination that would
substantially contribute towards
 Diagnosis
 Treatment
 Assesment of progress of disease
WE PERFORM CT SCAN IN SUSPECTED MENINGITIS BEFORE LP IF
ONE OR MORE RISK FACTORS ARE PRESENT
 ALTERED MENTATION
 FOCAL NEUROLOGICAL SIGNS
 PAPILLEDEMA
 SEIZURES WITH IN PREVIOUS WEEK
 IMPAIRED CELLULAR IMMUNITY

6. CONTRAINDICATIONS
ABSOLUTE
• LOCAL SEPSIS
• SPACE
OCCUPYING
LESION WITH
RAISED ICT
RELATIVE
• PAPILLEDEMA
• BLEEDING
DIATHESIS
PLATELTS LESS
THAN 50000
SEVERE
PULMONARY
AND
RESPIRATORY
DIFFICULTY

7. TECHNIQUE OF LUMBAR PUNCTURE

9. COMPLICATIONS OF LP
 POST LP HEAD ACHE
 INFECTION
 BLEEDING
 CEREBRAL HERNIATION
 MINOR NEUROLOGICAL SYMPTOMS LIKE RADICULAR PAIN AND NUMBNESS
 BACK PAIN
 DIPLOPIA
SUSPECT HERNIATION?
DETERIORATION OF CONSCIOUSNESS IMMEDIATELY OR WITH IN 12 HRS
NECK STIFFNESS
DILATED PUPILS
BRADYCARDIA

10. NORMAL VALUES OF ADULT CSF
Opening pressure 50–200 mm H2O CSF (range in
literature)
Color Colorless
Turbidity Crystal clear
Mononuclear cells Less than 5 per mm3
Polymorpho nuclear cells 0
Total protein
Glucose
22–38 mg/dL
60–80% of blood glucose

11. Measuring intracranial pressure
 Connect to manometer after successful tap rapidly in order to
avoid significant fluid loss that can falsly lower csf pressure
 If opening pressure is above normal; rule out causes for falsely
elevated pressure.
 abdominal compression either due to position or anxiety with a
consequent tensing of the abdominal musculature.
 Gently straighten the legs. In majority, the pressure will
decrease to normal. If it does not, then distract the patient
 A pressure upto 230 may be found in normal obese patients.
 Pressure cannot be assessed by simply observing the speed with
which the csf drips out of the needle.manometer must always
be used.

12. High pressure csf
Intra cranial neoplasms
Meningitis
Sub arachanoid haemorrhage
Low pressure csf
• Faulty placement of needle in which abdominal
compression cause no rise
• Below the level of complete spinal block

13. Examination of fluid
 Hold the container first upto the light and then
against a white surface.
 Normal CSF: Clear & colorless
 Viscosity : Equal to water
 Turbid CSF- Bacteria, WBCs cells or pus cells:
suggestive of a CNS infection (menigitis or
encephalitis)
 Blood : suggestive of hemorrhage: subarachnoid or
artifactual traumatic tap: DIFFERNTIATE?

14.  Yellow colour
1- Jaundice (bilirubin in CSF)
2- Xanthochromia: CSF suggests that a subarachnoid
hemorrhage has recently occurred (at least within 6
hours prior to tapping).
The yellow color is due to bilirubin generated in the
CNS by the breakdown of hemoglobin released from
RBC's. (so jaundice should be excluded).
3- rarely highly proteinaceous fluid

15. Cells
 An infection of the nervous system produces three basic CSF types
Type A
• WBC-500–20,000,90% neutrophils,
• low CSF sugar,
• protein elevated to 100–500 mg/dL.
Type B
• 25–500 WBC,mononuclear cells (but may be PMLs early in the
course of disease)
• low or occasionally normal CSF sugar
• protein of 50–500 mg/dL,characteristic of tuberculosis and
other granulomatous meningitides
Type C
• 5–1,000 WBC/mm3,mononuclear pleocytosis (may be PMLs
early)
• normal glucose(rarely quite low)
• protein less than 100 mg/dL.

16. Type A
Bacterial meningitis
Primary amoebic meningoencephalitis: rare
condition caused by free-living amebas. The classic
epidemiology,absence of organisms on gram stain and eventually
on culture, hemorrhagic component to the fluid should promptly
suggest the diagnosis, which can be confirmed by wet mounts of
the CSF revealing motile trophozoites
Ruptured brain abscess : diagnosed by a gram stain
showing
multiple types of organisms, an extremely high protein
level
and isolation of multiple organisms including
anaerobes.

17. TYPE B
Tuberculosis
Fungal meningitis: produced by a variety of fungi; the
most common are cryptococci, histoplasma, coccidioides and
candida.seen in immuno-suppressed
Sarcoidosis :often has meningeal involvement. Te
characteristic picture is a mild to moderate pleocytosis that is
almost mononuclear, in the range of 10–300 WBC/mm3, mild
to moderate protein elevation (between 50 mg/dL and 200
Meningeal carcinomatosis : crux of the diagnosis is the
demonstration of neoplastic cells in the CSF. Te most common
primary tumors reported to cause meningeal carcinomatosis are
breast carcinoma, lymphomas, lung carcinoma and pancreatic carcinoma.
Csf protein is markedly elevated.

18. Type c fluid
Parameningeal infections
Listeria monocytogenes meningitis is peculiar gram-positive
rod with characteristic “tumbling motility”
Secondary syphilis
Toxoplasmosis
Herpes simplex virus 1 (HSV-1) meningoencephalitis,
Viral meningitis enteroviruses account for over 50% of
cases. Other agents include flaviviruses, mumps, herpes
simplex, lymphocytic choriomeningitis (LCM) and the
human immunodeficiency virus (HIV).
Human immunodeficiency virus

19. CSF Glucose
- Normal CSF glucose: 50-80 mg/dl
- The actual CSF glucose concentration may be:
1- Falsely low in the presence of hypoglycemia
2- Incorrectly interpreted as normal when the patient is hyperglycemic
-Accordingly, CSF glucose should always be compared with a
simultaneous
plasma glucose that is drawn prior to lumbar puncture.
Normal CSF glucose/ plasma glucose ratio is approximately 0.6-0.7
(N.B. Ratio is decreased if plasma glucose is more than 500 mg/dl
due to saturation of the glucose carrier system to CSF

20. Elevated CSF / plasma glucose ratio (more than 0.7)
has no CSF diagnostic significance (occurs with hyperglycemia)
Decreased CSF / plasma glucose ratio(hypoglycorrhachia):
1- CNS septic (pyogenic) infections
Due to increased glycolysis by leukocytes and bacteria (with
increase CSF lactate)
2- Brain tumors
due to increased metabolism of glucose by CNS
3- TB meningitis & sarcoidosis
Due to inhibition of glucose entry into the subarachnoid
space
N.B. in viral CNS infections, CSF glucose is usually normal

21. CSF PROTEINS
 Cerebrospinal fluid proteins are derived from serum
proteins with the exception of trace proteins and
some beta globulins.
 Certain proteins arise within the intrathecal
compartment:
1- Immunoglobulins produced by CNS lymphocytes
2- Transthyretin (produced by choroid plexus)
3- Various structural proteins found in brain tissue

22. Three conditions can cause abnormalities of
the CSF proteins:
Increased entry of plasma proteins due to
increased permeability of blood-brain
barrier
 Local synthesis of proteins within the CNS
 Impaired resorption of CSF proteins.

23. Decreased CSF protein:
Leak of CSF from a tear in the dura due to
severe trauma
 Otorrohea: leak of CSF from ear
Rhinorrohea: leak of CSF from nose

24. Increased CSF protein:
 Lysis of contaminant blood from traumatic tap (each
1,000 rbc/mm3 raise the csf protein 1.5mg/dl)
 Increased permeability of epithelial membrane (blood-brain
barrier)
- CNS bacterial or fungal infections
- Cerebral hemorrhages
 Increased production by CNS tissue as in cases of:
- Multiple sclerosis (MS)
- Subacute sclerosing panencephalitis (SSPE)
 Obstruction as in cases of :
- Tumors or abscess

25. Analysis of protein fractions: (Albumin & IgG)
 1- Albumin of CSF
is obtained from blood by means of blood-brain barrier (as it is
produced solely by the liver)
In cases of increased permeability of BBB, albumin is increased in
CSF
 2- IgG of CSF can be obtained:
from blood (By BBB) : increase in cases of increase permeability of BBB
& by local synthesis from plasma cells within CSF (increased in cases of
MS)
So, it is essential to determine the source of IgG

26.  FIRST: CHECK INTEGRITY OF BLOOD BRAIN BARRIER (BBB)
BY CSF / serum albumin index calculation
CSF serum albumin index = CSF albumin (mg/dl) / serum albumin (g/dl)
Index less than 9 indicates intact BBB (no increased permeability of BBB)
 SECOND: CSF IgG INDEX IS CALCULATED
CSF IgG / Serum IgG
CSF IgG index = ---------------------------------------
CSF albumin / serum albumin
Normal : less than 0.7
Increased in cases of demylineating diseases of CNS as : Multiple sclerosis (MS)

27. CSF Immunoglobulin
CSF IgG/Serum IgG
CSF serum /Albumin index
 CSF IgG can arise:
1)from plasma cells within CSF
2) from the blood through BBB
CSF IgG index:
Normally: < 0.7
=
 ↑CSF [IgG] without concomitant ↑ in CSF [Alb] suggests local
production of IgG:
 multiple sclerosis (MS)
 subacute sclerosing panencephalitis (SPEE)

28. CSF Electrophoresis: Oligoclonal Banding

29. CSF lactate
CSF lactate is increased in cases of bacterial
meningitis (due to increased glycolysis by bacteria &
inflamatory cells)

30. CSF glutamine
The level of CSF glutamine reflects level of ammonia
in that is normally removed in the CNS by formation of
glutamine (amino acid glutamate + ammonia).
Glutamine synthesis helps to protect the CNS from the
toxic effects of increased ammonia.
Ammonia production is increase dramatically in
patients with liver failure.
Accordingly, CSF glutamine production is increased in
cases of hepatic encephalopathy

31. Enzymes in the CSF
CSF lactate dehydrogenase (LDH) may be
elevated in bacterial meningitis.
CSF adenosine deaminase (ADA)
elevations can occur in tuberculous
meningitis.

32. Other Chemical Components of
CSF
 CSF [Calcium], [Potassium] & [Phosphates] are lower
than their levels in the blood
 CSF [Chloride] & [Magnesium] are higher than their
levels in the blood
 Abnormal CSF [Chloride]
 marked  in acute bacterial meningitis
 slight  in viral meningitis & brain tumors

33. Interpretations of Results of CSF
Chemical Analysis
Bacterial
Meningitis
Viral
Meningitis
Tuberculous
Meningitis
Brain Tumor
Protei
n
Increased Normal Increased Increased
Glucose Decreased
Normal
or
slightly
affected
Decreased Decreased

34. THANK YOU