Correlation of early MRI with CT scan, EEG, and CSF: analyses in a case of biopsy-proven herpes simplex encephalitis.

Herpes simplex encephalitis (HSE) carries a high mortality rate. Therefore, an early diagnosis and institution of acyclovir are essential. We report a case of biopsy-proven HSE with 2 negative cerebrospinal fluid (CSF) analyses and 2 normal CT scans. However, MRI together with EEG were abnormal early in the disease stressing their significant role in any suspected case of HSE. Although brain biopsy remains controversial, CSF herpes simplex antigen detection offers hope in providing an early or retrospective diagnosis while specific antiviral therapy with acyclovir is initiated. Overdependency on routine CSF analysis or head CT scan can result in unnecessary delays in diagnosis and treatment.