RESUMO
Although West Nile virus (WNV) serologic evidence has been well demonstrated throghout Turkey in the last 40 years; the first symptomatic WNV infection was reported in 2009 and increased number of cases were reported during August 2010. In that period WNV encephalitis was diagnosed serologically (WNV IgM positivity in serum sample detected by ELISA and IFA) and confirmed by plaque reduction neutralization test in a 76-year-old man who was admitted to Baskent University Faculty of Medicine with complaints of fever, impaired consciousness and generalized tremors. Despite all supportive treatment, he died on the 9th day of hospitalization. In this report, detailed clinical course, laboratory features and diagnosis of this mortal case of WNV encephalitis were described. WNV encephalitis should be considered in the differential diagnosis of patients with fever of unknown origin and loss of consciousness especially in summer and early fall in Turkey.