TABLE 94.9 CAUSES OF ASEPTIC MENINGITIS Viral Enteroviral Herpes simplex virus Arboviral Lymphocytic choriomeningitis virus Mumps Other viral infections Bacterial Early or partially treated bacterial meningitis Parameningeal infection Mycobacterium tuberculosis Borrelia burgdorferi (Lyme disease) Rickettsial diseases Bartonella henselae (cat scratch) Leptospirosis Treponema pallidum (syphilis) Mycoplasma Fungal Cryptococcus Histoplasmosis Parasitic Candida Naegleria Toxoplasmosis Taenia solium (neurocysticercosis) Malaria Trichinosis Noninfectious Neoplasia Kawasaki disease Hemorrhage Collage vascular diseases Hypersensitivity reactions Heavy metal poisoning Sarcoidosis Because the CSF findings in aseptic meningitis overlap those in bacterial infections, hospital admission is usually warranted until the CSF culture results are available However, the experienced clinician may choose to follow the older child as an outpatient if the family is reliable and nonviral causes (e.g., Lyme disease, tuberculosis, cryptococcosis) are clinically unlikely To guide clinicians, the Bacterial Meningitis Score has been derived and validated to identify children at very low risk (negative predictive value 99.7%) for bacterial meningitis Low-risk features are negative CSF Gram stain; CSF absolute neutrophil count (ANC)