[PS6-1B-1] Limbic Encephalitis – Role of Infectious Pathogens and Antineuronal Antibodies
Limbic encephalitis refers to non-viral inflammation, mainly involving the limbic system, including the mediotemporal lobes, amygdala, and cingulate gyrus. It is defined by clinical symptoms, such as retrograde amnesia, temporal lobe seizures, or psychiatric symptoms, and by radiological evidence, such as nonatrophic hyperintensity of the mediotemporal lobes at early course, or by detection of antibodies associated with limbic encephalitis. Because of the possibility of herpes simplex virus encephalitis, most patients with subacute limbic encephalitis are started on acyclovir. Therefore, to differentiate the underlying etiology is very important. Furthermore, virus infection as a disease trigger is a possible mechanism for the brain inflammation.
Early identification of potential patients who have antineuronal antibodies to intracellular or neuronal surface antigens in order to give appropriate immunotherapy is keys to improving the prognosis. We enrolled children and adolescents who had been hospitalized due to non-viral limbic encephalitis. Serum samples from these patients were collected to screen antibodies against intracellular antigens (amphiphysin, Ma2, Ri, Yo, Hu and anti-glutamic acid decarboxylase [GAD]) and neuronal surface antigens (N-methyl-D-aspartate [NMDA] receptor, γ-amino butyric acid [GABAB] receptor, voltage-gated potassium channel complexes [VGKCs]). All of the 10 enrolled patients had acute onset of fever and rapid clinical deterioration. All of them had persistent neuropsychiatric symptoms and 90% developed refractory epilepsy despite 6 patients having been treated with methylprednisolone pulse therapy or intravenous immunoglobulin at the acute stage. In the laboratory findings, half of the cases were positive for antibodies with regards to intracellular antigens (amphiphysin or GAD).
Early identification of potential patients who have antineuronal antibodies to intracellular or neuronal surface antigens in order to give appropriate immunotherapy is keys to improving the prognosis. We enrolled children and adolescents who had been hospitalized due to non-viral limbic encephalitis. Serum samples from these patients were collected to screen antibodies against intracellular antigens (amphiphysin, Ma2, Ri, Yo, Hu and anti-glutamic acid decarboxylase [GAD]) and neuronal surface antigens (N-methyl-D-aspartate [NMDA] receptor, γ-amino butyric acid [GABAB] receptor, voltage-gated potassium channel complexes [VGKCs]). All of the 10 enrolled patients had acute onset of fever and rapid clinical deterioration. All of them had persistent neuropsychiatric symptoms and 90% developed refractory epilepsy despite 6 patients having been treated with methylprednisolone pulse therapy or intravenous immunoglobulin at the acute stage. In the laboratory findings, half of the cases were positive for antibodies with regards to intracellular antigens (amphiphysin or GAD).