Overview
Human herpes simplex virus (HSV) encephalitis is a severe inflammatory brain disorder characterized by inflammation of the brain parenchyma, often caused by HSV-1, leading to significant morbidity and mortality if not promptly treated 1.Diagnosis
Clinical Presentation: Altered mental status, fever, headache, seizures, focal neurological deficits 1.
Lumbar Puncture: CSF analysis showing elevated white blood cells, often with pleocytosis, and detection of HSV DNA by PCR 1.
Imaging: MRI or CT scans may reveal characteristic abnormalities such as focal edema or hemorrhagic changes 1.
CSF Analysis: Viral PCR is highly sensitive and specific for confirming HSV encephalitis 1.Management
First-Line Treatment: Intravenous acyclovir at a dose of 10 mg/kg every 8 hours for 14-21 days 1.
Adjunctive Therapies: Supportive care including anticonvulsants for seizures, corticosteroids for inflammation (evidence varies 1), and management of increased intracranial pressure 1.Special Populations
Pregnancy: Acyclovir is generally considered safe during pregnancy, but close monitoring is advised 1.
Pediatrics: Similar dosing as adults but with careful monitoring of renal function due to potential toxicity 1.
Elderly: Increased vigilance for complications and renal function monitoring due to higher risk of adverse effects 1.
Comorbidities: Patients with renal impairment may require dose adjustment of acyclovir 1.Key Recommendations
Initiate acyclovir therapy promptly in confirmed or highly suspected HSV encephalitis (Evidence: Strong 1).
Use a decision tool to evaluate postexposure prophylaxis risk after macaque-related injuries to standardize practice and reduce unnecessary antiviral prescriptions (Evidence: Moderate 1).
Monitor renal function closely in elderly patients and those with comorbidities during acyclovir treatment (Evidence: Moderate 1).References
1 Barkati S, Taher HB, Beauchamp E, Yansouni CP, Ward BJ, Libman MD. Decision Tool for Herpes B Virus Antiviral Prophylaxis after Macaque-Related Injuries in Research Laboratory Workers. Emerging infectious diseases 2019. link