infection of subarachnoid disease

1. Meningitis
Dr Bhupendra Shah

2. Why we need to know it?
• Medical emergency
• High prevalence
• Early recognition is must

3. Objectives
• Definition
• Causative agent
• Pathogenesis
• Clinical features
• Investigations
• Management

4. Definition
• Meningitis:
• Meningo-encephalitis:
• Brain abscess:

5. Common bacterial organisms
Organsism Age range Predisposing condition
N.Meningitidis All ages Usually none
S.Pneumonia All ages Cribiform plate fracture
Listerial monocytogenes Elderly adults and neonates Defects in cell mediated
immunity ,pregnancy
Coagulase negative
stap.aureus
All ages Surgery
Gram negative bacilli Elderly ,neonate Advanced medical illnness
H .influenza Adult Diminished humural
immunity.

6. Pathogenesis:
Dvasogenic edema Obstructive edema
FfAltered blood brain
barrier permeability
Raised intracranial
pressure and coma
Cytotoxic edema
Dproduction of
excitatory amino acid
Dfleukocytes adherence to
cerebral capillary
endothelial cell
Subarachnoid space invasion by meningeal pathogens
Release of bacterial cell wall components

7. Clinical features
• Fever
• Altered mental status
• abnormal jerky movements
• Neck stiffness
• Headache

8. History of…..
• Immuno-compromised status
• Ear discharge
• Body rashes
• Head trauma/surgery

9. Physical examination
• Neck rigidity
• Kernig’s sign
• Brudzinski’s sign
• Head jolt test

10. Kernig’s sign

11. BRUDZINSI’S SIGN

12. Rash of menigococcemia

13. Normal CSF finding
• Apperance :clear
• Opening pressure:10-12 cm H2O
• WBC count:0-5 /mm3
• Glucose :>60% of serum glucose
• Protein:< 45 mg/dl

14. Lumbar puncture

16. Ct scan of head

17. Empiric antimicrobial therapy
<1 months Ampicillin +cefotaxime
1-23 months Vancomycin +3rd generation cephalosporin
2-50 yrs Vancomycin +3rd generation cephalosporin
>50 yrs Vancomycin +ampicillin+3rd generation cephalosporin
Basillar skull fracture Vancomycin +3rd generation cephalosporin
Post neurosurgery Vancomycin +cefepime
Immunocompromised Vancomycin +ampicillin+cefepime

18. Prophylaxis for meningococcal
meningitis
• Rifampin 600 mg bd for 2 days
• Azithromycin 500 mg single dose
• Ceftriaxone 250 mg IM single dose

19. Steroids in meningitis
merits
• Inhibit synthesis of TNF
• Decrease CSF flow
resistance
• Stabilise the blood brain
barrier
demerits
• Delays sterilisation of CSF
fluid
• Hippocampal injury thus
reducing learning capacity
20 minute prior antibiotics.
Dexamethasone 0.15mg/kg qid 3-4 days

20. Other causative agent
• M.tuberculois • Herpes simplex virus

21. Summary
• Meningitis is medical emergency
• Mortality approach to 100% if untreated.
• CBC,2 set blood cultures,CSF analysis,CT scan.
• Antibiotics:proper timing
:proper antibiotics
:proper duration