Results of cerebrospinal fluid (CSF) analysis were as follows: WBC count, 36/μL with lymphocytic predominance (93%); RBC count, 19/μL; glucose level, 75 mg/dL (normal); and protein level, 29.8 mg/dL (normal). CSF Gram stain and blood cultures were negative for bacteria, fungus, and mycobacteria. Additional serum and CSF serologies were negative for cysticercosis, Lyme disease, syphilis, legionella, Bartonella, Brucella, Q fever, Ehrlichia, and Rocky Mountain spotted fever. Viral serologies were negative for herpes simplex, cytomegalovirus, John Cunningham virus, Epstein-Barr virus, varicella-zoster virus, West Nile virus, HIV, and Saint Louis and eastern and western equine encephalitis. Histoplasma urine antigen test results were normal.