To analyze clinical, imaging, and laboratory findings, and outcomes of cerebrovascular manifestations of herpes simplex virus (HSV) infection.

Intracerebral hemorrhage and ischemic stroke are increasingly recognized complications of central nervous system (CNS) infection by HSV.

Systematic literature review from January 2000 to July 2018.

We identified 38 patients (median age 45 years, range 1-73) comprising 27 cases of intracerebral hemorrhage, 10 of ischemic stroke, and one with cerebral venous sinus thrombosis. Intracerebral hemorrhage was predominantly (89%) a complication of HSV encephalitis located in the temporal lobe. Hematoma was present on first brain imaging in (32%), and hematoma evacuation was performed in 30% of these cases.

Infarction was frequently multifocal, and at times preceded by hemorrhage (20%). Both a stroke-like presentation and presence of HSV encephalitis in a typical location were rare (25% and 10%, respectively). There was evidence of cerebral vasculitis in 63%, which was exclusively located in large-sized vessels.

Overall mortality was 21% for hemorrhage and 0% for infarction. HSV-1 was a major cause of hemorrhagic complications, whereas HSV-2 was the most prevalent agent in the ischemic manifestations. 

We found a distinct pathogenesis, cause and outcome for HSV-related cerebral hemorrhage and infarction. Vessel disruption within a temporal lobe lesion caused by HSV-1 is the presumed mechanism for hemorrhage, which may potentially have a fatal outcome. Brain ischemia is mostly related to multifocal cerebral large vessel vasculitis associated with HSV-2, where the outcome is more favorable.