J Clin Neurol.  2016 Apr;12(2):224-229. 10.3988/jcn.2016.12.2.224.

Prognostic Value of Initial Standard EEG and MRI in Patients with Herpes Simplex Encephalitis

• Kim YS
• Jung KH
• Lee ST
• Kang BS
• Yeom JS
• Moon J
• Shin JW
• Lee SK
• Chu K

• KMID: 2354144
• DOI: http://doi.org/10.3988/jcn.2016.12.2.224

Abstract

BACKGROUND AND PURPOSE
Herpes simplex encephalitis (HSE) is the most common type of sporadic encephalitis worldwide, and it remains fatal even when optimal antiviral therapy is applied. There is only a weak consensus on the clinical outcomes and prognostic factors in patients with HSE. This study examined whether the radiological and electrophysiological findings have a prognostic value in patients with HSE.
METHODS
We retrospectively analyzed patients who were diagnosed with HSE by applying the polymerase chain reaction to cerebrospinal fluid and who received intravenous acyclovir at our hospital from 2000 to 2014. We evaluated the clinical outcomes at 6 months after onset and their correlations with initial and clinical findings, including the volume of lesions on MRI, the severity of EEG findings, and the presence of epileptic seizures at the initial presentation.
RESULTS
Twenty-nine patients were enrolled (18 men and 11 women). Univariate analysis revealed that the presence of severe EEG abnormality and epileptic seizures at the initial presentation were significant correlated with a poor clinical outcome at 6 months (p=0.005 and p=0.009, respectively). In multivariate analysis, the presence of severe EEG abnormality was the only independent predictor of a poor outcome at 6 months (p=0.006).
CONCLUSIONS
In cases of HSE, the initial EEG severity and seizure presentation may be useful predictive factors for the outcome at 6 months after acyclovir treatment.

Keyword

herpes simplex virus; encephalitis; polymerase chain reaction; electroencephalography

MeSH Terms

Acyclovir
Cerebrospinal Fluid
Consensus
Electroencephalography*
Encephalitis
Encephalitis, Herpes Simplex*
Epilepsy
Herpes Simplex*
Humans
Magnetic Resonance Imaging*
Male
Multivariate Analysis
Polymerase Chain Reaction
Retrospective Studies
Seizures
Simplexvirus
Acyclovir

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