Non-paraneoplastic Autoantibody-negative Limbic Encephalitis Characterized by Mild Memory Impairment: A Case Report

Encephalitis that primarily involves limbic system structures such as the hippocampus and parahippocampal gyrus has been described in early papers, most commonly characterized by a subacute progressive impairment of short-term memory, psychiatric features and seizures. While these findings might be caused by viral infections or systemic autoimmune disorders, many patients with limbic encephalitis have an immune-mediated etiology (paraneoplastic or not) characterized with serum or CSF antineuronal antibodies. This case reports about non-paraneoplastic autoantibody-negative limbic encephalitis in which there are no detection of antigens and no evidence of tumors.