To date, no formal studies have assessed the duration of adequate immunosuppression. to immune therapy, with prompt diagnosis and treatment strongly beneficial. Patients with paraneoplastic encephalitis are more refractory to treatment compared to those in whom no malignancy is identified. Herein, the authors present an update of literature data on the clinical presentation, laboratory and imaging findings, therapy, and outcomes for the most common autoimmune encephalitides. strong class=”kwd-title” KEYWORDS: em Autoimmune /em , em children /em , em encephalitis /em , em limbic /em , em N-Methyl-D-aspartic acid /em , em paraneoplastic /em INTRODUCTION em A /em utoimmune encephalitides (AE) are more frequent of individual viral etiologies, but the exact prevalence of individual disorders remains largely unknown.[1] In pediatric ages, AE usually occurs in females, as in adults, less probable TC-E 5001 with a cancer association (more common in adults), and a history of other antibody-mediated condition is frequent. Several antibodies have been demonstrated to be associated with paraneoplastic and nonparaneoplastic neurological syndromes, divided into three groups: (1) antibodies to intracellular antigens; (2) to cell-surface antigens; (3) to extracellular synaptic antigens. PEDIATRIC AUTOIMMUNE ENCEPHALITIDES WITH ANTIBODIES TARGETING NEURONAL CELL-SURFACE ANTIGENS Anti-N-Methyl-D-aspartic acid encephalitis First described in 2007,[2] it is the most frequent and best characterized AE. Autoantibodies of IgG subclass G1 bind the extracellular domain of the GluN1 subunits of the N-Methyl-D-aspartic acid receptor (NMDAR), with its internalization, resulting in the surface underexpression.[3] Herpes TC-E 5001 simplex virus encephalitis (HSVE) is an important trigger for anti-NMDAR encephalitis. The so-called post-HSVE choreoathetosis in children is confirmed now as post-HSVE anti-NMDAR encephalitis. The manifestations of anti-NDMAR encephalitis can be categorized into eight groups: abnormal behavior and cognition; memory deficit; speech disorder; seizures; abnormal movements (orofacial, limb, or trunk dyskinesias); loss of consciousness or autonomic dysfunction; central hypoventilation;[4] cerebellar ataxia or hemiparesis. Fever and headache are prodromal symptoms without specificity. In children, behavior problems, seizures, and movement disorders are most common. Electroencephalogram (EEG) is abnormal, typically showing focal or diffuse slowing and/or epileptiform discharges. An EEG pattern known as extreme delta brush has been described in anti-NMDAR encephalitis and may support the diagnosis.[5] Brain magnetic resonance imaging (MRI) demonstrates abnormalities in less than half of all pediatric patients,[6] including cortical and/or subcortical, basal ganglia, and infratentorial T2 hyperintensities with or without transient meningeal enhancement. Rarely, children with a demyelinating pattern have been reported.[7] Pathogenic anti-NMDAR autoantibodies can be present both in serum and cerebrospinal fluid (CSF), with the latter a more sensitive detection. The CSF antibody titers correlate strongly with the clinical disease course and remain elevated in those who experience a relapse or do not show primary clinical improvement.[8] Anti-NMDAR antibodies production can be stimulated by an underlying tumor and the most frequently associated is ovarian teratoma that must be removed for optimal recovery. Prompt immunotherapy improves patient outcome.[9] The prognosis is often good in pediatric age, with 85% of full but slow recovery (up to several months) and relapse in the remaining 15%. Encephalitides with leucine-rich glioma-inactivated 1 and contactin-associated protein-like 2 antibodies These disorders were previously attributed to antibodies to voltage-gated potassium channels (VGKCs), but the true target antigen has been shown to be its tightly associated neuronal proteins leucine-rich gliomas-inactivated 1 (LGI1) and contactin-associated protein-like 2 (Caspr2). In these encephalitides, high titer of VGKC-complex antibodies may Rabbit Polyclonal to ITGB4 (phospho-Tyr1510) be present; although this finding is not relevant, in consideration that it is a not specific marker of inflammatory neurologic affections. LGI1-AE shows a limbic syndrome (confusion, working memory deficit, mood changes, and often seizures), hyponatremia, and occasional faciobrachial dystonic seizures; in Caspr2 – AE Morvan syndrome and neuromyotonia may be present. In adult, some cases are paraneoplastic and the most common associated tumor is thymoma; however, there are currently no published reports of TC-E 5001 childhood neoplasm in these encephalitides. CSF is regular or only displays oligoclonal often.