Out of Time: Altered Mental Status And Temporal Seizure On Background of Dementia & UTI

Herpes simplex virus is common in the US, with an estimated seroprevalence of HSV-1 of 40% and HSV-2 of 11%. Although herpes encephalitis is rare, with an incidence of roughly 1/100,000 individuals per year in the US, the mortality rate of 70% and rapid progression make identification and treatment imperative. An 85 year old woman was brought to the emergency department from nursing home with altered mental status of unknown duration in refractory status epilepticus on a background of dementia, history of multiple falls, and indwelling foley catheter in addition to hypertension and bilateral knee replacement. EEG demonstrated abnormal discharges in the right anterior temporal region on a background of diffuse slowing, consistent with temporal encephalitis; MRI showed no acute intracranial abnormality. Urinalysis demonstrated moderate bacteria in the urine and blood cultures demonstrated presence of Staphylococcus epidermidis and Streptococcus anginosus. CSF was negative for HSV1 and HSV2 IgG and IgM, but Meningitis Film array panel demonstrated HSV-1. The patient failed to improve after 5 days of acyclovir and the family opted for inpatient hospice. This case demonstrates the importance of multiple diagnostic methods, as reliance on MRI and CSF PCR alone would have missed this fulminant progression. Additionally, acyclovir is recommended over valacyclovir by the Antimicrobial Stewardship Program.