The University of Toledo Translation Journal of Medical Sciences 
Infectious Diseases Abstract, Department of Medicine Research Symposium UTJMS 2023 May 5; 11(1):e1-e1 

Herpes Simplex Virus-1 Encephalitis 
Secondary to Whole Brain Radiation 
Therapy 
Andrew Waack, M21*, Sarah Jaggernauth, M21, James Iordanou, DO1, Venkatramana 
Vattipally, MD1, Claudiu Georgescu, MD1

1Division of Infectious Diseases, Department of Medicine, The University of Toledo, 
Toledo, OH 43614 

*Corresponding author: Andrew.waack@rockets.utoledo.edu

Published: 05 May 2023 

Background: Encephalitis is inflammation of the brain parenchyma with associated neurological 
dysfunction. Herpes simplex virus-1 (HSV-1) encephalitis (HSE) is the most common cause of 
encephalitis. HSV-1 characteristically remains dormant in the trigeminal ganglion and reactivates during 
states of immunosuppression, including stress, cancer or chemotherapy. There have been few reported 
cases of HSE following whole brain radiation therapy (WBRT) for treating intracranial tumors. 
Importantly, reported HSE cases following WBRT demonstrate an atypical presentation of encephalitis. 
We report a case of HSE following WBRT to treat brain metastases of renal cell carcinoma.   

Case Presentation: A 67-year-old female patient who recently underwent WBRT to treat brain 
metastases from renal cell carcinoma presented with an elevated temperature, weakness and altered 
mental status. The patient was admitted, and baseline CT imaging did not demonstrate any acute 
abnormalities. The next day the patient’s neurological status declined substantially, prompting MR 
imaging that revealed lesions in the temporal lobes, encompassing the amygdala and hippocampus 
bilaterally. Extra limbic lesions were also demonstrated. Empirical intravenous acyclovir was initiated 
upon suspicion of possible HSE. Later imaging revealed cerebellar folia enhancement, suggesting 
probable leptomeningeal carcinomatosis. CSF PCR was positive for HSV-1, confirming the diagnosis of 
HSE. The patient’s condition significantly improved and ultimately returned to baseline.   

Conclusion: We present a case of HSE following WBRT. HSE must be promptly treated to avoid 
catastrophic outcomes. However, rapid treatment may be difficult due to a delay in diagnosis, which is 
difficult due to the atypical presentation of HSE secondary to WBRT. 

https://dx.doi.org/10.46570/utjms.vol11-2023-762 

https://dx.doi.org/10.46570/utjms.vol11-2023-762
mailto:Andrew.waack@rockets.utoledo.edu