Immunoperoxidase demonstration of herpes simplex virus type 1 in the brain of a psychotic patient without history of encephalitis.

A 75-year-old female with a remote history of electroconvulsive-shock therapy and more recent care for psychotic depression died due to thromboembolic disease. Intranuclear inclusions were found to be widespread in her brain after autopsy. There was a paucity of the usual pathologic findings of herpes simplex virus (HSV) encephalitis, but light microscopic studies using antiserum to HSV type 1 demonstrated the presence of this agent in the intranuclear inclusions and in the cytoplasm of neurons and glial cells using immunoperoxidase staining methods. Immunostaining was also performed at the ultrastructural level and virus-like particles were identified. No immunostaining was obtained using normal control serum or antiserum to HSV type 2, while HSV type 1 or type 2 was demonstrated by immunostaining in control tissues. Control brain tissue from a group of psychotic and non-psychotic patients failed to show immunostaining for HSV antigen. This case is discussed in light of the current evidence pointing to a link between viral disease and psychosis.