Viral meningoencephalitis

© 2011 Sociedad Española de PEDIATRÍA Extrahospitalaria y Atención Primaria (SEPEAP). Central nervous system (CNS) infections can present as meningitis, encephalitis, or meningoencephalitis, depending on the involved CNS area. Viruses are the most frequent cause with enterovirus, followed by herpes viruses, paraechovirus, some respiratory viruses and arbovirus being the commonest causes. There is a peak of incidence in children under one year of age and also in children between 5 and 10 years, mainly during summer and autumn. Systemic symptoms are usually unspecific and CNS involvement may vary depending on the causative virus. A fast evaluation of the patient is mandatory, through the anamnesis, physical examination and complementary tests as cerebroespinal fluid analysis, imaging and electroencephalogram. The differential diagnosis is established mainly with other CNS infections, autoimmune encephalitis and other encephalopathies. The prognosis is variable depending on the affected area and the causative virus. It is advisable to follow up on these patients after the disesase have resolved. General higiene and the vaccination in specific cases are the most important prevention measures.