Neurosyphilis vasculitis manifesting as ischemic stroke.

A 26-year-old man presented with acute-onset right hemiparesis, diplopia on horizontal gaze, and fever. Brain magnetic resonance imaging (MRI) with high-resolution vessel wall imaging (HR-VWI) showed left hemipons infarction and concentric parietal thickening of the basilar artery, consistent with vasculitis (Figures 1 and 2). Cerebrospinal fluid and blood samples were positive for syphilis on the Venereal Disease Research Laboratory (VDRL) test and Treponema pallidum particle agglutination assay. A test for human immunodeficiency virus was positive (viral load: 188,330 copies/mL) and his CD4+ count (248 cells/mL) was below the reference range (500-1,450 cells/mL). The patient was administered intravenous penicillin G for 21 days as well as highly active antiretroviral therapy. The serum VDRL test result fell in response to treatment and a VDRL test of his cerebrospinal fluid revealed negative results. The patient was discharged 21 days after admission with residual right hemiparesis and diplopia.

FIGURE 1:

Axial DWI and T2-weighted MRI showing left hemipons infarction (arrows, A and B). Three-dimensional time-of-flight magnetic resonance angiography showing significant stenosis of the basilar artery (arrow, C).

FIGURE 2:

Post-contrast axial and sagittal HR-VWI showing concentric parietal thickening and enhancement of the basilar artery consistent with a vasculitic pattern (arrows, A and B). Post-contrast sagittal HR-VWI also reveals enhancement of the left abducens nerve (arrow, C).

Neurosyphilis can occur at any stage of the disease and may be associated with occlusive large vessel infarcts - . In such cases, MRI with HR-VWI can be useful for diagnosing stroke and depicting vessel wall inflammation associated with infectious vasculitis.