We report a case of concomitant West Nile virus (WNV) encephalitis and acute ischemic strokes and review the literature documenting cases of WNV encephalitis with associated cerebrovascular disease.
Cases of WNV have risen since 2002, but neuroinvasive disease in uncommon, occurring in 1 in 150. The most common presentation of neuroinvasive WNV is a meningo-encephalitis. Cerebrovascular presentations are exceedingly rare.
We report a case of concomitant neuro-invasive WNV infection and acute stroke. We include magnetic resonance imaging (MRI), serologic and cerebrospinal fluid (CSF) laboratory data, and electroencephalogram (EEG) findings. We also present a review of PubMed, Embase, and Web of Science databases for cases of WNV encephalitis associated with cerebral infarctions.
A 70-year-old woman without significant cardiovascular history was admitted with depressed level of consciousness, hypophonia, and inability to participate in examination. MRI and computed tomography angiography demonstrated bilateral corona radiata strokes without obvious large vessel occlusion. Transthoracic echocardiogram demonstrated a patent foramen ovale; lower extremity ultrasound did not reveal any venous thrombosis. Low-density lipoprotein was elevated. Urine toxicology screen was positive for cocaine. Poor mental status could not be explained by the infarcts alone thus further testing was pursued. Testing for toxic and metabolic abnormalities was unrevealing. EEG demonstrated mild generalized delta slowing. CSF testing showed elevated WNV IgM and IgG. Upon discharged to a rehabilitation facility, her examination was unchanged from presentation. A review of the literature yielded 28 cases of WNV encephalitis complicated by cerebrovascular disease. Most cases were multi-territorial ischemic strokes but etiology of infarction appears varied.
Pursuit of uncommon etiologies is imperative when presenting symptoms and imaging are not explained by routine testing. The association of neurotropic viruses and strokes may be underappreciated, and possible pathophysiologic connections remain unexplained.