Herpes simplex virus limbic encephalitis in a Filipino man with advanced stage testicular cancer: A case report

Abstract

A 66-year-old Filipino Male, Hypertensive, Diabetic, diagnosed with Advanced Testicular Cancer presented with a five day history of fever, productive cough associated with sudden onset of behavioral changes, memory lapses and disorientation. On admission, the patient was disoriented, with poor comprehension and inability to follow commands. There were no focal motor deficits or signs of meningeal irritation. Cranial CT scan and serum electrolytes were unremarkable. CBC showed leukocytosis with predominant neutrophils, chest xray revealed pneumonia. Piperacillin+ Tazobactam and Azithromycin was started On the second hospital day, he had seizures manifested as blank stares, teeth grinding, lip smacking and fidgety movement of the right hand. Electroencephalogram showed epileptiform discharges in both frontal-prefrontal and both frontal-central regions. A cranial MRI with Contrast revealed high T2W and FLAIR signal changes and edema in the mesial temporal lobes and right insula (Figure 1) and right lentiform nucleus (Figure 2). EEG and MRI findings are consistent with Limbic Encephalitis based on the diagnostic criteria by Gultekin et al.1(2014). A lumbar puncture yielded a colorless cerebrospinal fluid (CSF) with normal opening pressure, normal RBC and WBC, lymphocytic predominance (96%), elevated CSF protein and normal CSF glucose. CSF Acid Fast Bacilli (AFB), KOH and India Ink were all negative. Further CSF analysis for neuronal autoantibodies specifically Anti-NMDA, Anti- Hu and Anti- Ma2 were likewise negative. Polymerase Chain Reaction (PCR) assay for Herpes Simplex Virus was positive for HSV-1. Intravenous Acyclovir was started at 15mg/kg per day. After three weeks of antiviral therapy the patient's condition improved.