Clinical Spectrum and CSF Findings in Patients with West-Nile Virus Infection, a Retrospective Cohort Review.

West Nile Virus (WNV) infection is a world-wide zoonotic disease transmitted by mosquitoes. The infection is usually self-limiting; however, elderly patients or those with comorbidities are predisposed to developing severe, and sometimes fatal complications of the infection. Recently, the incidence of WNV infection in Europe had seen a sharp increase, as compared to previous years. We are currently reporting on the clinical presentation and laboratory findings in 23 cases of WNV infection, of which one resulted in a fatal outcome. The clinical picture was predominantly that of meningitis/meningoencephalitis of varying severity. One patient suffered a fatal outcome, and a rare manifestation of chorioretinal lesions and iridocyclitis was also reported as a result of WNV infection. Cerebrospinal fluid analysis predominantly showed lymphocytic pleocytosis, and total protein levels were increased in all but three of the patients. Levels of total protein in CSF samples were found to show a positive correlation with age. Given the ever-increasing incidence of WNV infection in Europe, a high index of clinical suspicion should always accompany cases of meningitis, especially during the summer period, as a similar epidemic pattern is predicted to recur.