By Prof. Dr. Rao Suhail Yasin Khan
Consultant Neurologist, Advanced International Hospital (AIH), Islamabad

Introduction

• Brain infections such as meningitis and encephalitis are life-threatening emergencies requiring early recognition and treatment.
• These infections can be caused by bacteria, viruses, tuberculosis, or autoimmune processes.
• Delay in diagnosis can lead to irreversible brain damage, seizures, coma, or even death.
• At AIH, we frequently manage complex cases involving neuro infections with a multidisciplinary approach.

Understanding Meningitis

• Meningitis is the inflammation of the meninges (the protective layers around the brain and spinal cord).
• Bacterial meningitis is more severe and demands urgent antibiotic therapy.
• Common bacterial causes:
  • Streptococcus pneumoniae
  • Neisseria meningitidis
  • Haemophilus influenzae (HiB)
• Viral meningitis tends to be milder, often caused by enteroviruses.

Symptoms:

• High-grade fever
• Severe headache
• Neck stiffness
• Nausea, vomiting
• Sensitivity to light (photophobia)
• Altered mental status in severe cases

Understanding Encephalitis

• Encephalitis is the inflammation of brain tissue itself.
• Most often caused by viruses such as:
  • Herpes Simplex Virus (HSV)
  • Japanese Encephalitis Virus
  • Dengue virus
• Other causes include autoimmune encephalitis, especially in young patients.

Symptoms:

• Fever and confusion
• Behavioral changes or hallucinations
• Seizures
• Focal neurological deficits
• Coma in severe cases

Tuberculous Meningitis

• Common in Pakistan due to high TB prevalence.
• Often has a gradual onset with symptoms such as:
  • Persistent low-grade fever
  • Night sweats
  • Chronic headache
  • Vomiting
  • Drowsiness
• Diagnosis requires high suspicion and specialized CSF testing.
• Early anti-tubercular therapy and steroids are critical for survival.

Autoimmune Encephalitis

• Caused by antibodies attacking the brain (e.g., anti-NMDAR, LGI1).
• Often misdiagnosed as psychiatric illness or viral encephalitis.
• Common in young adults or children.
• Responds well to steroids, IVIG, or plasma exchange.
• Early diagnosis can reverse symptoms dramatically.

Diagnostic Evaluation

• Lumbar puncture (spinal tap) is essential:
  • Measures CSF pressure
  • Analyzes cell count, glucose, protein
  • PCR to detect viral or TB DNA
• Neuroimaging (MRI) helps identify inflammation or abscess.
• EEG useful in encephalitis with seizures or altered awareness.
• Blood cultures, TB screening, autoimmune antibody testing may also be required.

Emergency Red Flags

• Seizures or status epilepticus
• Rapid loss of consciousness
• Severe headache with vomiting
• Focal weakness or paralysis
• Persistent fever with altered behavior
• Complications
• Post discharge care
• Follow ups
• Reoccurence possibility

Treatment Principles

• Start empirical treatment early — do not wait for full test results.
• For bacterial meningitis:
  • IV antibiotics (e.g., ceftriaxone + vancomycin)
  • Dexamethasone may reduce complications
• For viral encephalitis:
  • Immediate IV acyclovir if HSV suspected
  • Supportive care (hydration, fever control, seizure management)
• For TB meningitis:
  • Full anti-TB drug regimen
  • Corticosteroids for inflammation
• For autoimmune encephalitis:
  • High-dose steroids, IVIG or plasmapheresis
  • Treat underlying tumor if present (e.g., ovarian teratoma in NMDAR encephalitis)

Prognosis and Recovery

• Early treatment improves survival and outcome.
• Some patients recover fully; others may have long-term effects:
  • Memory problems
  • Epilepsy
  • Weakness or behavioral issues
• Tuberculous and HSV encephalitis carry higher risks of complications.
• Autoimmune encephalitis, when treated timely, has a very favorable outcome.

Prevention Strategies

• Vaccination is key:
  • HiB, pneumococcal, and meningococcal vaccines prevent bacterial meningitis.
  • Japanese encephalitis vaccine in endemic areas.
• Hygiene and mosquito control reduce viral encephalitis risk.
• TB control programs essential in our region.
• Raising awareness of autoimmune encephalitis is crucial.

Take Away Message

• Brain infections are neurological emergencies.
• Do not ignore fever with confusion or severe headache — it could be life-threatening.
• At AIH, we are equipped with modern diagnostics and ICU support for treating these conditions.
• Early consultation with a neurologist can save lives and prevent disability.

For any such symptoms or concerns, timely evaluation by a neurologist is essential. At AIH, we provide 24/7 neurological care with advanced diagnostics, ICU support, and personalized treatment protocols.