Case Reports of Neuroinvasive Manifestation of Viral Encephalitis

Abstract

West Nile virus (WNV) infection is a mosquito-borne viral disease, which can cause an inflammation of the brain and meningitis. WNV is commonly found in Africa, West Asia, the Middle East and Europe. For the first time in North America, WNV was confirmed in the New York metropolitan area during the summer and fall of 1999. Since then, WNV over-wintered in the northeastern United States and has been described in humans, horses, birds, and mosquitoes. It is estimated that more than 80% of infected persons remain asymptomatic. Of those who develop symptoms, 80–90% develop an uncomplicated, self-limited febrile illness (‘West Nile fever’; WNF) while the remaining persons develop severe diseases including West Nile meningitis (WNM), West Nile encephalitis (WNE), or an acute poliomyelitis- like syndrome. In fact, less than 1% patients will develop neuroinvasive disease, which typically manifests as meningitis, encephalitis, or acute flaccid paralysis [1]. We are presenting two cases admitted at our tertiary medical center-Vidant Medical Center in Eastern North Carolina with neuroinvasive WNV manifestation. Both patients presented with fever, altered mental status, and proceeded to develop respiratory failure. One patient died thirty days after admission and the other survived with residual isolated right lower extremity weakness that required prolonged rehabilitation.