Image Significance in the Diagnosis of Another Case of Herpetic Encephalitis

Herpes simplex virus 1 (HSV-1) causes necrotizing encephalitis, usually located in the temporal lobes and with a high mortality rate if not diagnosed and treated early. Cranial computed tomography (CT) scan, although not very sensitive, can help by highlighting hemorrhagic foci and edema in the frontotemporal lobes, given the tropism of the virus for these areas. We present the case of a 70-year-old male who came to the emergency department (ED) with fever and confusion. Despite an unclear cerebrospinal fluid (CSF) result, the CT scan showed a spot of hypodensity in the mesial aspect of the left temporal lobe. He was given 21 days of intravenous acyclovir, and his neurological condition normalized. These cranial CT alterations, although not pathognomonic, indicate a strong suspicion of herpetic encephalitis.