What is the dose of steroids (corticosteroids) for Tuberculous (TB) meningitis based on the Medical Research Council (MRC) grade?

Corticosteroid Dosing for TB Meningitis Based on MRC Grade

For tuberculous meningitis, adjunctive corticosteroid therapy with dexamethasone is strongly recommended, with dosing based on MRC grade: dexamethasone 0.4 mg/kg/day IV (maximum 12 mg/day) for adults, with initial treatment for 3 weeks followed by gradual tapering over 3 weeks. 1

Adult Dosing Regimen

• Dexamethasone is the preferred corticosteroid for TB meningitis, administered intravenously initially 1
• Initial dose: 0.4 mg/kg/day with maximum of 12 mg/day for adults 1
• Duration: Initial dose for 3 weeks, then gradually tapered over the following 3 weeks (total 6 weeks of therapy) 2, 1
• Alternative: Prednisolone 60 mg/day initially, tapered over 6-8 weeks 1

Pediatric Dosing Regimen

• For children weighing less than 25 kg: Dexamethasone 8 mg/day 2, 1
• For children weighing 25 kg or more: Dexamethasone 12 mg/day (same as adult dose) 2, 1
• Duration: Initial dose for 3 weeks, then gradually decreased over the following 3 weeks 2

MRC Grade-Specific Considerations

• MRC Grade I (alert and oriented): Corticosteroids still recommended though benefit may be less pronounced than in more severe disease 2
• MRC Grade II (lethargic): Greatest mortality benefit from corticosteroids (15% mortality with dexamethasone vs 40% without) 2
• MRC Grade III (comatose): Standard dosing recommended despite less clear mortality benefit in some studies 2, 1

Administration and Monitoring

• Corticosteroids should be initiated before or concurrently with the first dose of anti-tuberculosis medication 1
• Regular monitoring of cerebrospinal fluid parameters through repeated lumbar punctures should be considered, especially early in therapy 2, 1
• Some centers use a modified approach where patients can be shifted to oral steroids after 48 hours of sustained improvement on IV steroids 3
• Patients with basal exudate, tuberculoma, and modified Rankin scale <3 may be candidates for earlier transition to oral steroids 3

Evidence for Corticosteroid Use

• A Cochrane review found that corticosteroids reduce mortality from tuberculous meningitis by almost 25% (RR 0.75,95% CI 0.65-0.87) 4
• The mortality benefit may not persist at 5-year follow-up (RR 0.93,95% CI 0.78-1.12) 4
• Dexamethasone may reduce hydrocephalus and prevent infarction, particularly in the basal ganglia 5
• The benefit applies to both HIV-negative and HIV-positive patients, though data for HIV-positive patients are more limited 4

Anti-TB Treatment Duration

• Standard anti-TB therapy for meningitis should be continued for 9-12 months total 2, 1
• Initial phase: INH, RIF, PZA, and EMB for 2 months 2, 1
• Continuation phase: INH and RIF for an additional 7-10 months 2, 1

Potential Pitfalls

• Corticosteroid benefit may be underestimated in studies because the most severe patients often cannot be included in imaging studies 5
• Development of tuberculomas during therapy may represent a paradoxical reaction rather than treatment failure 2
• Visual monitoring is important when using ethambutol, particularly in unconscious (MRC Grade III) patients 2
• Adverse events from corticosteroids (gastrointestinal bleeding, bacterial infections, hyperglycemia) should be monitored but generally do not outweigh mortality benefit 4