Clues to the diagnosis include Time spent in wooded areas and travel to an endemic area (including in Europe) History of erythema migrans or other symptoms of Lyme disease Unilateral or bilateral facial palsy (common in Lyme disease but rare in most viral meningitides) Papilledema (well-described in children with Lyme disease but rare in viral meningitis) CSF findings typically include Lymphocytic pleocytosis Moderately elevated protein Normal glucose Diagnosis of Lyme disease is based on serologic tests with enzyme-linked immunosorbent assay (ELISA), followed by Western blot analysis to confirm.