Powerpoint on TB Meningitis.

1. Tuberculous Meningitis
SANJAY GEORGE

2. Epidemiology
 India has one fifth of the world’s TB burden.
 2 million new cases in 2009.
 Around 10% develop CNS disease.

3. Etiology
 Mycobacterium tuberculosis.
 Risk Factors:
 Delay in diagnosis and treatment
 HIV, Immunocompromised state.

4. Pathophysiology
 50% cases : History present, Hematogenous spread
 Seed meninges or brain – Sub-pial/Sub-ependymal foci of
metastatic caseous lesion – Rich Foci.
 Proximity to S.A Space determines type of CNS involvemeny.
 Rupture into S.A space – Meningitis
 Deep in parenchyma cause Tuberculoma or Abscesses.

5. Contd.
 Paresis of C.N nerves common as involvement more at base of
brain.
 Disease evolves over 1-2 weeks.
 Thick gelatinous exudate infiltrates the cortical, meningeal blood
vessels, producing inflammation, obstruction, or infarction.
 Ultimate evolution to coma, with hydrocephalus and intracranial
hypertension.

8. Clinical Features
 Headache
 Vomiting
 Low Grade Fever
 Malaise, Anorexia, Irritability
 Severe Headache
 Confusion
 Lethargy
 Altered Sensorium
 Neck Rigidity
Initially
Late

9. Signs
 Meningism (maybe absent)
 Occulomotor palsies
 Papilloedema
 Depression of conscious level
 Focal hemisphere signs.

10. Differential Diagnosis
 Other Infectious causes of meningitis
 Acute hemorrhagic leukoencephalopathy
 Behçet disease
 Chemical meningitis
 Chronic benign lymphocytic meningitis
 Neoplastic: metastatic, lymphoma
 Systemic lupus erythematosus
 Vascular: Multiple emboli, subacute bacterial endocarditis, sinus
thrombosis
 Vasculitis
 Vogt-Koyanagi-Harada syndrome

11. Investigations
 Lumbar Puncture:
 High leucocyte count (upto 1000/μL) with lymphocytic predominance.
 Elevated Protein (100-800 mg/dL).
 Mildly Decreased Glucose Concentration (20 – 40 mg/dL)
 AFB – 1/3rd cases
 CSF culture (Gold Standard) – diagnostic in 80% cases.
 PCR
 Imaging Studies – MRI, CT

12. Management
 Initiate if high index of suspicion.
 Initial Therapy:
 Isoniazid – 300mg/d
 Rifampicin – 10mg/kg/d
 Pyrazinamide – 30mg/kg/d
 Ethambutol – 15-25 mg/kg/d
 Pyridoxine – 50mg/d
 Good Response : Discontinue Pyrazinamide after 2 months continue
H & R for 6 – 12 months
 Inadequate Resolution : Continue for 9 – 12 months
 Dexamethasone in HIV –ve Patients. 12 -16mg/day for 3
weeks, tapered over next 3 weeks

13. Contd.
 Obstructive hydrocephalus and neurological deterioration :
ventricular drain or ventriculoperitoneal or ventriculoatrial shunt.
 Prevention:
 BCG Vaccine