Opsoclonus: an early sign of neonatal herpes encephalitis.

Preferential involvement of certain central nervous systems areas by specific viruses provides a valuable guide to the selection of antiviral agents. We report a neonate that developed opsoclonus 7 days prior to the diagnosis of herpes simplex type 2 cerebellitis. The course of the opsoclonus paralleled the clinical course and radiologic evolution of the infection. The purpose of this report is to describe opsoclonus as a possible early sign of herpes simplex type 2 central nervous system infection.