Herpes simplex virus 2 vasculitis as cause of ischemic stroke in a young immunocompromised patient

Herpes simplex virus 2 (HSV-2) is a very rare cause of central nervous system (CNS) infections. We report a case of a young woman with a left middle cerebral artery (MCA) ischemic stroke. The patient had history of HIV-1 infection, with periods of therapeutic non-compliance. Initial computed tomography (CT) imaging studies showed stenosis of the M1 segment of the left MCA, and magnetic resonance imaging (MRI) confirmed infarction of the MCA territory. Serial transcranial Doppler ultrasound revealed progressive occlusion of the MCA and stenosis of the left anterior cerebral artery. Systemic investigation for other causes of stroke was normal. Lumbar puncture revealed a mildly inflammatory cerebrospinal fluid, and HSV-2 DNA was identified by PCR, with a positive viral load in favor of active replication. No other viral or microbiological infections were identified. MRI angiography confirmed a vasculitic process involving the left carotid artery, and a HSV-2 vasculitis diagnosis was assumed. The patient started acyclovir with improvement of clinical features and imaging abnormalities. In the HIV-infected patient, stroke is a multifactorial common cause of morbidity. The physician should take into account a broad differential diagnosis including rare causes and atypical presentations of common etiologies, including HSV-1 and HSV-2 CNS infection.