Case report
Herpes Simplex Virus Encephalitis Presenting as Acute Hemiplegia and Altered Sensorium: A Case Report
OD31-OD33
Correspondence
Deepak Raj,
No. 40/68, TVK 2nd Link Road, Kodungaiyur, Chennai-118, Chennai, Tamil Nadu, India.
E-mail: deepakraj.maa@gmail.com
Herpes Simplex Virus Encephalitis (HSVE) is the most common cause of sporadic fatal viral encephalitis worldwide and carries substantial morbidity and mortality when antiviral therapy is delayed. The disease typically involves the temporal lobes and presents with fever, altered mental status, seizures, and focal neurological deficits. However, early clinical and radiological features may closely resemble acute ischemic stroke, leading to diagnostic uncertainty. We report a 46-year-old male patient who presented with an acute onset of fever, global aphasia, right-sided hemiplegia, and altered sensorium. Magnetic Resonance Imaging (MRI) demonstrated unilateral cortical T2/FLAIR hyperintensity with diffusion restriction predominantly involving the left temporal and fronto-parietal regions, without conformity to a specific vascular territory. Electroencephalography (EEG) revealed Periodic Lateralised Epileptiform Discharges (PLED) over the left hemisphere. Normal opening pressure, slight lymphocytic pleocytosis (68 cells/mm3), normal protein and glucose, and negative Gram stain, AFB smear, and fungal investigations were all observed in the CSF study. A normal first CSF does not rule out the diagnosis because early HSVE might appear with little or normal CSF abnormalities. Empirical intravenous acyclovir was initiated promptly. The patient demonstrated neurological stabilisation following antiviral therapy. This case highlights the importance of considering HSVE in patients presenting with acute febrile focal neurological deficits mimicking stroke. Early recognition and timely antiviral therapy significantly reduce mortality and improve neurological outcomes.