Early detection in suspected herpes simplex encephalitis.

In a retrospective study of ten patients who had brain biopsy because of suspected herpes simplex encephalitis, the diagnosis was confirmed in only three patients. However, in four patients whose clinical presentation was indistinguishable from that of 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.