What are the complications of Tuberculosis (TB) meningitis?

Complications of Tuberculous Meningitis

Tuberculous meningitis causes severe neurological and systemic complications in the majority of patients, with hydrocephalus, stroke, and hyponatremia being the most common life-threatening problems that directly impact mortality and long-term disability.

Acute Neurological Complications Requiring Immediate Recognition

Hydrocephalus (Most Common Structural Complication)

• Hydrocephalus occurs in 42-80% of TB meningitis patients and is the single most important surgically treatable complication 1, 2, 3.
• Develops due to thick gelatinous basal exudates blocking CSF flow pathways 3.
• Neurosurgical referral is mandatory for hydrocephalus, tuberculous cerebral abscess, or paraparesis 1.
• For obstructive hydrocephalus, placement of an external ventricular drain is indicated 1.
• Hydrocephalus significantly increases mortality and poor outcomes 2.
• May present initially or develop paradoxically after starting anti-TB treatment 3.
• Predictive factors include visual impairment, cranial nerve palsy, and basal exudates on imaging 2.

Cerebrovascular Complications

• Stroke occurs in 33% of TB meningitis patients and represents a major cause of permanent disability 4.
• Cerebrovascular complications include cerebral infarctions, subarachnoid hemorrhage, intracerebral hemorrhage, and venous sinus thrombosis 1.
• Basal exudates encase and strangulate vessels of the circle of Willis, causing ischemic injury 3.

Seizures

• Epileptic seizures occur in 28% of patients during acute illness 4.
• Seizures contribute to both acute morbidity and long-term epilepsy (11% of survivors) 4.

Cranial Nerve Palsies

• Cranial nerve involvement occurs in 29% of patients 4.
• Visual impairment and optic nerve/chiasm involvement are particularly concerning as they predict hydrocephalus development 2, 3.

Critical Metabolic Complications

Hyponatremia

• Hyponatremia is the most common metabolic complication, occurring in 49% of patients 4.
• Requires aggressive monitoring and correction to prevent cerebral edema and herniation 5.

Diabetes Insipidus and Hypothalamic Dysfunction

• Diabetes insipidus occurs in 6% of patients 4.
• Hypothalamic syndrome occurs in 3% 4.
• Both reflect direct hypothalamic-pituitary axis involvement by basal inflammation 4.

Parenchymal Complications

Tuberculomas

• Tuberculomas occur in 3% of patients and may require neurosurgical intervention if causing mass effect 4.
• Can develop paradoxically during treatment 3.

Myeloradiculopathy

• Spinal cord and nerve root involvement occurs in 3% of cases 4.
• Represents extension of basal meningeal inflammation to spinal compartment 4.

Long-Term Sequelae Impacting Quality of Life

Cognitive Impairment

• Cognitive impairment is the most common long-term sequela, affecting 12% of survivors 4.
• Represents permanent neurological damage from inflammation, infarction, and hydrocephalus 4.

Chronic Epilepsy

• 11% of long-term survivors develop chronic epilepsy requiring ongoing antiepileptic therapy 4.

Severe Disability and Mortality

• Overall mortality reaches 22% despite treatment 4.
• At follow-up, 1% remain in persistent vegetative state, 13% have severe disability, and 12% have moderate disability 4.
• Approximately 50% of patients die or suffer serious long-term sequelae 4.

Treatment-Related Complications

Hepatotoxicity

• Hepatotoxicity from anti-TB drugs is the most common iatrogenic complication 4.
• Requires monitoring of liver function and potential modification of treatment regimen 6.

Imaging and Monitoring Requirements

When to Obtain Cranial Imaging

• MRI is preferred over CT for superior resolution when intracranial complications are suspected 1.
• Obtain imaging for neurological deterioration, focal deficits, or decreased mental status 1.
• Look specifically for hydrocephalus, basal exudates, tuberculomas, and infarcts 2.

Role of Repeated Lumbar Puncture

• Routine repetition of lumbar puncture has limited yield and is not indicated 1.
• Consider only in selected cases with specific clinical questions 1.

Critical Management Principles to Prevent Complications

Adjunctive Corticosteroids

• Dexamethasone or prednisolone tapered over 6-8 weeks reduces mortality (strong recommendation, moderate certainty) 1.
• This represents the single most important adjunctive therapy proven to improve outcomes 1.

Treatment Duration

• Extended treatment for 9-12 months total is required (2 months intensive phase followed by 7-10 months continuation) 1.
• Shorter courses are inadequate for CNS tuberculosis 1.

Common Pitfalls to Avoid

• Failing to recognize hydrocephalus early leads to preventable herniation and death—maintain high suspicion and obtain imaging promptly 2, 3.
• Delaying neurosurgical consultation when hydrocephalus or mass lesions are identified increases mortality 1.
• Inadequate monitoring for hyponatremia can precipitate acute neurological deterioration 5, 4.
• Not counseling patients and families about the high risk (78%) of complications and need for long-term follow-up 4.
• Assuming clinical improvement means no complications—paradoxical worsening with new hydrocephalus or tuberculomas can occur after treatment initiation 3.