Herpes simplex encephalitis: two fatal cases.

The clinical and pathological features of the first two reported cases of herpes simplex encephalitis occurring in Saskatchewan are presented. The clinical history of an acute onset, an early organic mental syndrome followed by coma, neurologic disturbances, rapid progression and death suggests the diagnosis. The acute, diffuse, inflammatory process with predominant involvement of the temporal lobes of the cerebral hemispheres and the presence of intranuclear inclusions in nerve and glial cells are illustrated. The viral particles were found in electron micrographs from the brain tissue of both patients. The definitive diagnosis was established by the isolation, from postmortem brain tissue, of the herpes simplex virus, which was grown in tissue culture and shown to be pathogenic in suckling mice.