Impact of Obesity on Clinical Outcomes in Patients Receiving Acyclovir for HSV Encephalitis"

Inclusion Criteria: * Patients Admitted to a SSM Health - St. Clare (STL), St. Mary's (STL), Saint Louis University Hospital (STL), St. Anthony's (OKC), St. Mary's Madison (WIS), Rush University Medical Center (RUMC), or Methodist Dallas Medical Center * \> 18 years old * Positive cerebrospinal fluid (CSF) PCR for HSV-1 or HSV-2 * BMI \> 30 kg/m2 * Received guideline-approved, weight-based doses of IV acyclovir for HSV encephalitis for at least 72 hours during the index admission * Received appropriately renal dose-adjusted doses of IV acyclovir per package insert recommendations Exclusion Criteria: * More than one dosing weight strategy utilized for \> 24 hours for IV acyclovir dosing during the index admission * Patients transferred to the hospital already on IV acyclovir for HSV encephalitis * ESRD on admission * Concomitant pathogen causing meningitis or encephalitis * Oral acyclovir used for treatment