Persistent cerebrospinal fluid neutrophilia in delayed-onset neonatal encephalitis caused by herpes simplex virus type 2.

We describe an infant with three unusual features of perinatally acquired herpes simplex virus type 2 encephalitis: onset of illness at 34 days of age, absolute cerebrospinal fluid neutrophilia, and systemic viral dissemination after central nervous system disease. To provide early, effective antiviral therapy, clinicians should be aware of atypical presentations of serious herpes simplex virus infections.