Cerebrospinal fluid neutrophilic pleocytosis in hospitalized West Nile virus patients.

A description of 7 consecutive patients admitted for various forms of neurological impairment. All these patients were found to have cerebrospinal fluid positive for West Nile virus IgM, and routine bacterial cultures were negative. Six of these patients did not present with the typical lymphocytic pleocytosis often quoted when discussing a viral meningitis/encephalitis; rather most presented with a cerebrospinal fluid neutrophilia.