Cerebrovascular complications and vasculopathy in patients with herpes simplex virus central nervous system infection

Objective: Herpes simplex viruses (HSV) are neurotropic and known to cause central nervous system (CNS) infections. We aimed to describe the clinical and imaging features of cerebrovascular complications in patients with HSV CNS infections. Methods: We reviewed records of patients with HSV infections by querying acyclovir use in a clinical registry of parenteral anti-infective therapy at a tertiary medical center from January 2010 until September 2018. One patient who met the inclusion criteria is subsequently added. Diagnostic criteria for HSV CNS infection were intrathecal presence of viral DNA with clinical signs of CNS involvement. Results: Of 36 patients who met the criteria for HSV CNS infections, cerebrovascular complications occurred in 6 patients (17%). Two patients with HSV-1 encephalitis had cerebrovascular complications (1 ischemic stroke, 1 intraparenchymal hemorrhage). Four patients had HSV-2 infection without encephalitis had cerebrovascular complications (3 ischemic strokes, 1 cerebral vein thrombosis). All 3 patients with ischemic strokes without encephalitis had pattern of vasculitis on vessel imaging on MRI with segmental narrowing and vessel wall irregularities of large intracranial arteries with circumferential wall enhancement. Conclusion: Cerebrovascular complications of HSV can occur with encephalitis or as isolated events with vasculitis.