As of October 2023, there are a total of 542 cases of WNV with 298 cases reported as neuroinvasive, making Colorado the leading state of reported WNV in the US. We have encountered 3 unique clinical presentations of neuroinvasive WNV acting as mimics to stroke, seizure and botulism.  

Case 1 

41 year-old male presented with BLE weakness and numbness (L>R). Lumbar MRI showed juxtacortical edema with possible STIR hyperintensities, concern for infarction of the cord. He underwent an angiogram to further evaluate and results showed attenuated distal ASA with limited flow to conus, truncated R L2 segmental artery, consistent with spinal cord infarct. Patient regained strength in his legs. Repeat imaging showed resolution of signal abnormalities. His WNV was positive. 

Case 2 

66 year-old male presented with progressive diffuse weakness over the course of 5 days and ileus. Initial concern over NMJ pathology. Patient was treated with IVIG and Botulinum antitoxin but later developed necrosis of the basal ganglia and was found to have west nile encephalitis in addition to Botulism. 

Case 3  

19 year-old female presenting with fever and altered mental status. Initial LP was traumatic with bland CSF results. Meningioencephalitis panel negative. bMRI notable for DWI with ADC correlate changes in the corpus callosum. Clinically patient was presenting with posturing, concerning for seizure. EEG negative seizure was on the differential. Patient found to have WNV. 

 This case series highlights the difficulty in diagnosing unique presentations of neuroinvasive WNV as it can mimic other common neurologic processes. Neuroinvasive WNV has a broad range of unique clinical presentations as well as imaging findings, making it the new great mimic.