What are the implications of encephalitis with leukopenia (low White Blood Cell (WBC) count)?

From the Research

Encephalitis with decreased white blood cell (WBC) count suggests viral encephalitis, particularly herpes simplex virus (HSV) encephalitis, which requires immediate treatment with intravenous acyclovir at 10 mg/kg every 8 hours for adults (dose adjusted for renal function) for 14-21 days, as supported by the most recent study 1.

Key Considerations

• The decreased WBC count (leukopenia) may indicate a viral infection or immunosuppression, which can predispose patients to opportunistic infections affecting the brain.
• Other viral causes to consider include West Nile virus, enterovirus, and arboviruses.
• Diagnostic workup should include lumbar puncture for CSF analysis, brain MRI, and EEG, as recommended by 2.

Management

• Treatment should begin empirically before confirmatory test results are available, as delays increase mortality, as emphasized by 3.
• Supportive care is essential, including:
  • Seizure prophylaxis with levetiracetam 500-1000 mg twice daily.
  • ICP monitoring if significant edema is present.
  • Management of fever with acetaminophen.
• The decreased WBC count may complicate the clinical picture by masking typical inflammatory responses and increasing susceptibility to secondary infections, so broad-spectrum antibiotics may be considered until bacterial causes are ruled out, as suggested by 4.

Prognosis and Outcome

• Early diagnosis and treatment of HSV encephalitis can significantly improve outcomes, as highlighted by 5.
• The prognosis for patients with encephalitis depends on various factors, including the underlying cause, promptness of treatment, and presence of complications, as discussed in 1.