1. CNS Infections

2. CNS Infections
 Meningitis
– Bacterial
– Viral
– Fungal
– Chemical
– Carcinomatous

3.  Encephalitis
– Bacterial
– Viral
 Meningoencephalitis
 Abscess
– Parenchymal
– Subdural
– Epidural

4. Bacterial Meningitis
 Streptococcus pneumoniae
 Niesseria meningitidis
 Hemophilus influenzae
 Listeria moncytogenes
 Group B streptococcus

5. Bacterial causes of meningitis
Age of onset Common Less common
Neonate G-vebacillia Listeria monocytogenes
Group B streptococci
Pre-school child H-influenzae Mycobacterium
N-meningitidis tuberculosis
St-pneumonia
Older child N-Meningitidis L monocytogenous
St-pneumonia T.B
Crypto
Adult St-pneumonia L monocytogenous
N-Meningitidis T.B
Crypto

6. Bacterial Menigitis
 Age less than 3 months
– Group B strep
- E. coli
– L. Monocytogenes
- Strep. pneumoniae

7. Bacterial Meningitis
 3 Months to 1 year
– S. pneumoniae
– H. influenzae
– N. meningitidis

8. Bacterial Meningitis
 Age 18 to 50 years
– S. pneumoniae
– N. meningitidis
– H. influenzae

9. Bacterial Meningitis
 Over age 50 years
– S. pnemoniae
– L. monocytogenes
– Gram (-) bacilli

10.  Symptoms
– Fever (hypothermia in children)
– Headache
– lethargy to coma
– Nausea
– Vomiting
- Constitutional symptoms

11.  Signs
– Altered mental status (lethargy to coma).
– Meningeal signs (neck stiffness, kering sign and
brudzinski sign).
- Focal neurological signs.
– Increased intracranial pressure ( papilledema,
nausea/vomiting, abducens palsies, bulging fontanelle
in infants
- Skin rash.
- Adrenal insufficiency.
- Signs of systemic diseases.

12. LP
 glucose and protein
 cell count and differential
 gram stain and rountine culture
 Cyrptococcal antigen
 AFB stain and culture
 VDRL, or viral studies (PCR)

13. CSF Characteristics
Bacterial Viral Fungal TB
Opening Elevated Slightly Normal Ususally
Pressure elevated or High high
Glu Very Low Normal Low Low
Pro Very high Normal High Very
High
Rbcs Few None None None
Wbcs 1000-100 <200 <50 500-1000
(c/mm3) 00

14. Treatment of Bacterial
Meningitis
 3rd generation cephalosporin
 Steroids – Dexamethasone IV q6 for 4 days
 Antpyertic
 Treatmebt of seizure
 Treatment of complications

15. Viral Meningitis
More common
Viruses: Enteroviruse,Mumps,
Influenza Herpes simplex
Treatment is supportive

16. Viruses causing acute
encephalitis
Common
Arboviruses
Enterovirsuses
HSV
Less common
CMV
EBV
HIV
Mumps

17. Viral Encephalitis
 Encephalitis (Meningoencephalitis)
– Altered mental status, fever, focal deficit and
seizures
– Herpes Simplex virus (catastrophic condition)
predictable to the medial temporal lobe
 Acyclovir (30-60mg/dl)
 Management of seizures
 Very high morbidity and mortality
 PCR diagnosis of CSF

18. Chronic & recurrent meningitis
Characteristic neurological syndrome for>4weeks with
Persistent inflammation in CSF (WBC>5/Ul)
Causes:1-Meningeal infection (Immunocompromised patients)
– Cryptococcus neoformans
– HIV
– M. tuberculosis
– M. avium
2-Malignancy (Carcinomatous meningitis)
Lung, breast
3-Noninfectious inflammatory disorder
4-Chemical meningitis
5-Parameningeal infections

19. Symptoms & signs of sub acute
and chronic meningitis
Symptom Sign
Chronic headache Sign of Meningeal irritation
Change in personality Altered mental status
Facial weakness Crainal nerve palsy
Double visions Papilledema,optic atrophy
Weakness Myelopathy,radiculopathy
Sensory symptoms Frontal lobe dysfunction
Sphincter dysfunction Ataxia

20. TB Meningitis
 Meningitis of subacute onset
 Fever, vomiting, drowsiness, illhealth, wt
loss, anorexia, sweating and focal dificits
 Meningeal signs, Papilodema and hyloid
tubercule
 antiTB
 Steroid for 4wks