in this slides, there is introduction of meningitis & detailed CSF findings.

1. MENINGITIS- Etiology & CSF
findings
DR KALPANA ARORA

2. MENINGITIS
Meningitis -inflammation of leptomeninges (pia-arachnoid)
classification:
a) Acute pyogenic - bacterial meningitis
b) Aseptic-viral meningitis
c) Chronic-bacterial, fungal

3. ETIOLOGY

4. ETIOLOGY
1) hematogenous spread- arterial route. retrograde (veins)
2) direct implantation
- traumatic
- iatrogenic via lumbar puncture
3) local extension - mastoid and frontal sinuses, infected tooth.
4) PNS into CNS-viruses-rabies, herpes zoster

6. Methods for obtaining CSF
A. Spinal tap/ lumbar puncture
 L₃-L₄ intervertebral space in adults, L₄-L₅
space in children to avoid injury to Conus
medularis which is lower in children.
B. Cisterna magna and ventricular tapping
to avoid injury to spinal cord

7. Normal values for Lumbar CSF in adults
1. Appearance Clear and colourless
2. Volume 90-150 ml
3. Pressure 60-150 mmH₂O
4. Glucose 50 – 80 mg/dl
5. Proteins 15 – 45 mg/dl
6. Cells 0-5 lymphocytes/cu.mm, Neutrophils & RBC
are absent
If opening pressure is >200 mmH₂O in a relaxed pt., not
more than 2 ml fluid should be withdrawn, a fall of 25-
50% of initial pressure is indicative of cerebellar
herniation or spinal cord compression above the
puncture site.

8. 1. Acute Pyogenic (Bacterial) Meningitis
Causative organisms vary with age of the patient
a) Neonates- E. coli, Strep. Pneumoniae, Listeria
monocytogenes
b) Infants and children – Haemophilus Influenzae
c) Adolescents and young adults - Neisseria meningitidis
d) Elderly – Strep.pneumoniae

13. GROSS:
 Accumulation of exudate in the sub-arachnoid
space
 Normally clear CSF becomes turbid or purulent
 Turbid fluid is particularly seen in the sulci and
the base of the brain
 Fibrinous coating over the ventricular walls and
containing turbid CSF
 Obstructive hydrocephalus d/t block in normal
CSF flow

14. CSF
i) cloudy or frankly purulent
ii) increased CSF pressure (>180mm H2O)
iii)  Total leucocyte count (10-10,000/cmm)
iv) neutrophils increased
v)  CSF protein concentration (>50mg/dl)
vi) markedly  glucose concentration (<40mg/dl)

17. Waterhouse-Friderichsen syndrome
- Results from meningitis-associated septicemia
- Organism – N.Meningitidis
- hemorrhagic infarction of the adrenal glands
- cutaneous petechiae
- common with menigococcal and pneumococcal meningitis

18. 2. Acute Aseptic/ Viral Meningitis
Actually a misnomer
a) refers to absence of any recognizable organism
b) viral etiology -
enterovirus,mumps,poliovirus,echovirus, coxsackievirus,
EBV, HSV, HIV.
c) clinical course is less fulminant, self limiting
CSF-
a) CSF glucose near normal
b) protein only moderately elevated
c) lymphocytosis
d) mild brain swelling & infiltration of the
leptomeninges with lymphocytes

19. Drug induced aseptic meningitis:
•NSAID
•Antibiotics
CSF :
- CSF is sterile
- glucose normal
- pleocytosis with neutrophils
-  CSF protein

20. CHRONIC BACTERIAL MENINGITIS
Tuberculous:
- Haematogenous spread from other sites
- Miliary TB

21. Subarachnoid space contains thick exudate
- Particularly prominent in the sulci and base of the brain
- Tubercles 1-2 mm diameter adjacent to blood vessels

26. Auramine Rodamine stain

27. - Dense fibrous adhesions in sub-arachnoid space
- Hydrocephalus, Cranial nerve palsies
CSF :
- moderate leucocytosis
- Lymphocytosis
- proteins markedly 
- glucose slightly  or normal
Complication- tuberculoma
-

28. FUNGAL MENINGITIS
immunocompromised individuals
- Usually blood borne
Eitiologic agents:
1. Candida albicans
2. Mucor
3. Aspergillus fumigatus
4. Cryptococcus neoformans
Cryptococcus Neoformans
- Debilitated / immunocompromised / AIDS
- Haematogenous dissemination from lungs

29. Three major patterns of fungal infections
1) Chronic meningitis
2) Vasculitis (thrombosis & infarcts): Mucor, Aspergillus
3) Parenchymal invasion
- Candida and Cryptococcus
-Candida  multiple micro abscesses

32. Parameter Normal value Pyogenic
Meningitis
TB
Meningitis
Viral Meningitis
Pressure
mm H₂O
50-150
Appearance Crystal clear
Coagulum -
Protein mg/dl 15-45
Glucose mg/dl 50-80(2/3rd of
serum)
Chloride mg/dl 720-760
bacteriology - Gram stain ZN stain
DLC Lymphocytes
0-5

33.  PCR
 CT and MRI may be considered as
adjunctive diagnostics tests but are
generally nonspecific and show
meningeal enhancement