Acute Viral Meningitis

Acute viral meningitis refers to inflammation of the meninges of the brain in response to a viral pathogen. Viruses cause meningitis, encephalitis, myelitis, or a combination of these, meningoencephalitis or encephalomyelitis. Viral meningitis is typically a self-limited disorder with no permanent neurologic sequelae. This chapter reviews the epidemiology, etiology, diagnosis, differential diagnosis, treatment, complications, and prognosis. Tables describe Wallgren’s criteria for aseptic meningitis, important arboviral infections found in North America, herpes family viruses and meningitis, classic cerebrospinal fluid (CSF) abnormalities with viral meningitis, Centers for Disease Control and Prevention criteria for confirming arboviral meningitis, basic CSF studies for viral meningitis, and etiology of CSF pleocytosis. Figures depict common causes of viral meningitis, nuchal rigidity, examination for Kernig sign, and Brudzinski sign for meningeal irritation. This review contains 4 highly rendered figures, 8 tables, and 17 references.