Continuous video electroencephalogram for herpes simplex encephalitis: a case report and literature review

• Published in: Acta epileptologica Vol. 2; no. 1; pp. 1 - 8
• Main Authors: Lin, Wanhui, Chen, Shenggen, Lin, Hanbin, Liu, Changyun, Huang, Huapin
• Format: Journal Article
• Language: English
• Published: London BioMed Central 29.07.2020; BMC
• Subjects: Antibiotics; Autoimmune diseases; Complications; Consciousness; Convulsions & seizures; Electroencephalography; Encephalitis; Herpes simplex virus encephalitis; Herpes viruses; Immunoglobulins; Magnetic resonance imaging; Medical imaging; Non-convulsive status epilepticus; Periodic lateralized epileptiform discharge; Plasma; Pneumonia; Proteins; Rhabdomyolysis; Urine; Video electroencephalogram
• ISSN: 2524-4434; 2524-4434
• DOI: 10.1186/s42494-020-00017-x

Abstract Background Electroencephalogram (EEG) is an important tool for the diagnosis of herpes simplex virus encephalitis (HSE). However, the diagnosis of non-convulsive status epilepticus (NCSE) in HSE is challenging without the help of continuous video EEG (CVEEG), and whether EEG is a predictor of outcome remains controversial. Case presentation A 63-year-old woman presented with a 5 day history of fever, coma and seizures. Results of EEG, magnetic resonance imaging and polymerase chain reaction (PCR) in cerebrospinal fluid (CSF) were suggestive of herpes simplex encephalitis-1 (HSE-1). Preliminary EEG showed periodic discharges at the prefrontal and temporal lobes, which were particularly synchronized with intermittent lip smacking movements, and the discharges were terminated by diazepam. After 2-week treatment with acyclovir, high-dose hormone pulse therapy and high-dose immunoglobulin therapy, the CSF was improved, but the patient’s consciousness became worsen, consistent with the diffuse slow waves in the delta range and low voltage of EEG activity. In the following 1 month, the patient had non-responsiveness to pain and sound as shown by CVEEG with diffuse slow waves. Sometimes paroxysmal very slow waves (0.5–1 Hz) were synchronized with intermittent paroxysmal eye movements, pupil abnormality, and sweating in the frontal area. After 2 months of treatment, the EEG abnormalities improved to have alpha rhythm. Conclusion The CVEEG not only helps identify NCSE but can also be used to monitor HSE progression.