The importance of brain biopsy in suspected herpes simplex encephalitis.

In a retrospective study of 10 patients who underwent biopsies because of suspected herpes simplex encephalitis, the diagnosis was confirmed in only 3 patients. However, in 4 patients whose clinical presentations were indistinguishable from herpes simplex encephalitis, biopsy revealed other treatable conditions. These findings, together with a review of the recent literature, indicate that brain biopsy is the appropriate way to evaluate such patients.