Acute Nonparaneoplastic Limbic Encephalitis in Childhood: A Case Series in Japan

Limbic encephalitis not associated with malignancy was investigated in Japanese children, with particular focus on clinical features distinct from adult cases. Clinical, laboratory, and radiographic findings were studied in pediatric nonparaneoplastic limbic encephalitis, based on a literature review and questionnaire-based analyses. Analysis of 14 cases revealed the predominance of seizure occurrence, disturbance in consciousness, and frequent extralimbic signs. The majority manifested antecedent febrile illnesses, suggesting the involvement of infection-induced autoimmunity targeted to neuronal antigens. These clinical observations indicate a child-specific phenotype of limbic encephalitis. Further studies on its immunopathogenesis are needed to determine whether childhood limbic encephalitis is a distinct subcategory.