Ischemic Stroke as the Initial Presentation of an Underlying Neuroinfectious Disease

Neuroinfectious cerebral vasculitis is a rare but potentially underrecognized cause of ischemic stroke. Its clinical and neuroimaging features may closely mimic those of common cerebrovascular disorders, posing a diagnostic challenge. We describe two patients who presented with ischemic stroke, one with an atypical presentation and the other with recurrent episodes, in whom advanced neuroimaging and cerebrospinal fluid (CSF) analysis were pivotal in establishing the diagnosis. A 55-year-old man presented with a two-month history of nonfocal symptoms and was found to have a right posterior cerebral artery infarct with multifocal intracranial stenoses. Syphilis serology was positive in both blood and CSF. High-resolution magnetic resonance vessel wall imaging (HR-VWI) demonstrated multifocal vessel irregularities suggestive of inflammatory vasculopathy, although the initial clinical suspicion was ischemic stroke. A 48-year-old woman presented with recurrent posterior circulation strokes and progressively worsening neurological symptoms. HR-VWI again revealed vessel irregularities, prompting further investigation with CSF analysis, which identified herpes simplex virus 2 (HSV-2). These cases highlight the importance of considering neuroinfectious etiologies in patients presenting with unexplained, multifocal, or recurrent ischemic strokes. Advanced neuroimaging techniques, such as HR-VWI, may help identify intracranial vasculitic changes and prompt further targeted investigations, including CSF analysis, which is essential for establishing a neuroinfectious diagnosis. Given the potentially treatable nature of these conditions, early recognition and initiation of pathogen-specific therapy, supported by a multidisciplinary approach, are essential to optimizing clinical outcomes.