key: cord-0040412-3kh09082 authors: Christy, Cynthia title: Meningitis, Viral date: 2009-05-22 journal: Pediatric Clinical Advisor DOI: 10.1016/b978-032303506-4.10205-6 sha: 1b3f6e0bc46bcf400a5372320e5fda56a21f5686 doc_id: 40412 cord_uid: 3kh09082 nan DEFINITION Viral meningitis is inflammation of the meninges caused by many different viruses. Aseptic meningitis ICD-9-CM CODE 047.9 Unspecified viral meningitis Most common in infants younger than 1 year. In temperate climates, most cases occur in summer and fall; cases occur year round in tropical and subtropical climates. Spread is from person to person, by the fecal-oral route, and through respiratory droplets. Incubation period is 4 to 6 days. Meningitis develops in less than 1 per 1000 infected persons. Arboviruses are usually accompanied by brain involvement ( Perform lumbar puncture to collect CSF for the following: Cell count: white blood cell (WBC) count of 50 to 500/mm 3 ; may be up to 1000/mm 3 Differential count: may be a polymorphonuclear WBC predominance early, but shift to mononuclear predominance usually occurs within 12 to 24 hours CSF glucose level: usually normal or mildly depressed CSF protein level: usually normal to mildly elevated Gram stain: negative for bacteria Cultures: negative for bacteria CSF, blood, rectal, and nasopharyngeal swabs should be collected for viral cultures. Paired serum specimens (day 0 and days 10 to 21) can be collected for antibody titer rises if cultures do not grow viruses or bacteria. History and clinical findings may require additional culture for mycobacteria, fungal, or protozoal infection. Atypical cells may require examination of cytopathology to exclude tumor. Enterovirus and herpes simplex virus infections can be confirmed by polymerase chain reaction (PCR). At least 65% to 70% of culture-negative CSF infections in patients with aseptic meningitis are enterovirus positive by PCR. Identification of specific viral pathogen is possible in as many as 55% to 70% of cases when consistent diagnostic methods are applied. Fluids Analgesics (avoid aspirin because of associated risk of Reye's syndrome) Need for hospital admission based on possibility of treatable bacterial disease, toxicity, and need for hydration and pain control Observation for seizures (rare) No specific antibiotic therapy is available for enteroviral disease, but there is some efficacy of intravenous gamma-globulin in agammaglobulinemic patients. Acyclovir is available to treat meningitis caused by herpes simplex virus. Antibiotics may be started empirically while awaiting results of bacterial cultures (see Meningitis, Bacterial in Diseases and Disorders [Section I]) if diagnosis unclear. Antibiotics should be given parenterally. Antibiotics may be used in some cases such as: a toxic looking patients, a CSF with high WBC counts, a young patient with an atypical or severe clinical presentation. Pleconaril is available for compassionate release for selected patients with enteroviral disease (i.e., antibody-deficient patients with chronic enteroviral infection). Prognosis depends on the cause. Most children with enteroviral meningitis recover completely. Ten percent have CNS complications, including focal seizures, weakness, and obtundation or coma. Infants in first few months of life may have an increased risk for problems with language and development. These infants need formal developmental evaluation at age 3 to 6 years. Most patients with viral meningitis can be treated by their primary care provider. Subspecialty consultation may be needed in complicated cases. Pediatric infectious disease Neurology The common presenting signs of fever, vomiting, headache, and irritability need careful assessment to exclude meningitis, especially in the young infant. The diagnosis is established by lumbar puncture CSF cell count and culture results. Parenteral antibiotics are not needed to treat viral meningitis but may be used empirically if bacterial meningitis cannot be reasonably excluded from the differential diagnosis. Wash hands thoroughly and frequently. For child-care centers, wash objects and surfaces with which children have contact with a diluted bleach solution regularly. Use 1 cup of chlorine-containing household bleach in 1 gallon of water. Parents should be educated about the usually good prognosis (this is cause specific and most true for enteroviral infection). The low risk of neurologic sequelae can be discussed. Parents should be aware that the child's hearing and neurodevelopmental status should be monitored. The Meningitis Foundation of America has a large amount of information on its web site (www.musa.org) that can be of considerable assistance to patients who have had meningitis or families who have had a family member with meningitis. Available at www.governmentguide Aseptic meningitis in infants <2 years of age: diagnosis and etiology Aseptic meningitis and viral meningitis Aseptic meningitis in infants younger than 2 years of age: acute illness and neurologic complications Aseptic meningitis and viral meningitis