Acute viral encephalitis in children: Clinical manifestations and diagnosis
- Hordur S Hardarson, MD
Hordur S Hardarson, MD
- Landspitali University Hospital
- Section Editors
- Sheldon L Kaplan, MD
Sheldon L Kaplan, MD
- Editor-in-Chief — Pediatrics
- Section Editor — Pediatric Infectious Diseases
- Professor and Vice Chairman for Clinical Affairs
- Baylor College of Medicine
- Gary R Fleisher, MD
Gary R Fleisher, MD
- Editor-in-Chief — Adult and Pediatric Emergency Medicine
- Section Editor — Pediatric Signs and Symptoms
- Egan Family Foundation Professor
- Harvard Medical School
- Douglas R Nordli, Jr, MD
Douglas R Nordli, Jr, MD
- Section Editor — Pediatric Neurology
- Chief of Neurology
- Children’s Hospital Los Angeles
- Vice Chair of Neurology
- USC Keck School of Medicine
Viral infection of the central nervous system most often leads to meningitis, meningoencephalitis, or encephalitis, in descending order of frequency . Encephalitis is inflammation of the brain parenchyma, manifest by neurologic dysfunction (eg, altered mental status, behavior, or personality; motor or sensory deficits; speech or movement disorders; seizure) .
Strictly speaking, encephalitis is a pathological diagnosis; however, in practice, most patients with encephalitis are diagnosed based on clinical manifestations of brain dysfunction and laboratory or imaging evidence of inflammation (ie, white blood cells in the cerebrospinal fluid and/or inflammation on brain imaging).
The clinical manifestations and diagnosis of viral encephalitis in children will be discussed here. The pathogenesis, etiology, treatment, and prevention of viral encephalitis in children are discussed separately. (See "Acute viral encephalitis in children: Pathogenesis, incidence, and etiology" and "Acute viral encephalitis in children: Treatment and prevention".)
Central nervous system (CNS) infections are described according to the site of infection:
●Encephalitis – Encephalitis is inflammation of the brain parenchyma and is associated with neurologic dysfunction. Characteristic clinical features include altered mental status (decreased level of consciousness, lethargy, personality change, unusual behavior), seizures, and/or focal neurologic signs, often accompanied by fever, headache, nausea, and vomiting . (See 'Clinical features' below.)
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- CLINICAL FEATURES
- Neonates and young infants
- Children and adolescents
- Physical examination
- Laboratory evaluation
- - Routine blood tests
- - CSF evaluation
- - Evaluation for other causes of encephalopathy
- - Identifying the specific pathogen
- DIFFERENTIAL DIAGNOSIS
- Other infections
- Autoimmune encephalitis
- Intracranial pathology
- INFORMATION FOR PATIENTS
- SUMMARY AND RECOMMENDATIONS