Neuropsychological Response to Immunotherapy in Patients with Suspected Rapidly Progressive Dementia Secondary to Autoimmune Encephalitis: Analysis of 17 Cases (P3.386)

Objective:To describe the neuropsychological profile of 17 patients with Autoimmune Encephalitis (AE), and to evaluate its usefullness in measuring therapy response in these patients. Background: AE is an underdiagnosed and potentially treatable type of encephalitis that can result from a number of autoimmune diseases. Few publications have addressed the neuropsychological profile of this disorder, and its clinical value. Methods: 17 patients with suspected AE evaluates at our center between 2010 to 2015 were included in this study. In all cases, the diagnosis was based on the clinical presentation, MRI findings, and blood and CSF laboratory test results. An extensive neuropsychological battery was administered in all patients before and after immunotherapy treatment. Treatment options included first-line immunotherapy (steroids or intravenous immunoglobulin) and second-line immunotherapy (rituximab or cyclophosphamide). Results:17 subjects were included in the study (age 59.76±13.83 years, education 13.79±3.39, 64.70[percnt] male, 94.11[percnt] right handed). 35.29[percnt] of the patients had positive serum VGKC antibodies, 17.64[percnt] had serum positive ATPO antibodies and 41.17[percnt] had medial bitemporal hyperintensities in their Brain MRI, compatible with limbic encephalitis. Median time until assessment was 6 months. Before treatment, Mini Mental State Examination score was 26.80±2.49; 43[percnt] had a cortico-subcortical cognitive deficit profile, 29[percnt] had a subcortical profile and 14[percnt] had a cortical profile. All patients had deficits in verbal episodic memory. 64.70[percnt] presented associated neuropsychiatric symptoms. After immunotherapy treatment was administered, 7 cases had a clinical and neuroimaging improvement, and Neuropsychological testing was repeated (mean time of 8 months, 4 patients shown an improvement in subjective memory, 6 patients shown an improvement in the recognition task of the episodic verbal memory battery. Conclusions: In this sample of AE patients, neuropsychological testing was useful to detect cognitive compromise and to guide therapeutic options. The cognitive observed profile was predominantly cortico-subcortical, and behavioural symptoms were highly prevalent. Disclosure: Dr. Rojas has nothing to disclose. Dr. Demey has nothing to disclose. Dr. Quiroga has nothing to disclose. Dr. Pantiu has nothing to disclose. Dr. Leon Cejas has nothing to disclose. Dr. Bonardo has nothing to disclose. Dr. Pacha has nothing to disclose. Dr. Martinez has nothing to disclose. Dr. Uribe Roca has nothing to disclose. Dr. Ollari has nothing to disclose. Dr. Fernandez Pardal has nothing to disclose. Dr. Reisin has received personal compensation for activities with Shire HGT.