Meningitis

Dr Bhupendra Shah

Why we need to know it?

• Medical emergency

• High prevalence

• Early recognition is must

Objectives • Definition

• Causative agent

• Pathogenesis

• Clinical features

• Investigations

• Management

Definition

• Meningitis:

• Meningo-encephalitis:

• Brain abscess:

Common bacterial organismsOrgansism 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.

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

Clinical features

• Fever

• Altered mental status

• abnormal jerky movements

• Neck stiffness

• Headache

History of…..

• Immuno-compromised status

• Ear discharge

• Body rashes

• Head trauma/surgery

Physical examination

• Neck rigidity

• Kernig’s sign

• Brudzinski’s sign

• Head jolt test

Kernig’s sign

BRUDZINSI’S SIGN

Rash of menigococcemia

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

Lumbar puncture

Ct scan of head

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

Prophylaxis for meningococcal meningitis

• Rifampin 600 mg bd for 2 days• Azithromycin 500 mg single dose• Ceftriaxone 250 mg IM single dose

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

Other causative agent

• M.tuberculois • Herpes simplex virus

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