Anti-leucine-rich Glioma Inactivated-1 Encephalitis Associated with Essential Thrombocythemia

• Published in: Internal Medicine Vol. 59; no. 2; pp. 271 - 275
• Main Authors: Yuan, Xiaoling, Man, Xiaoyan, Zhang, Jinbiao, Sun, Jijun, Liang, Jianhua, Ma, Hongling, Tao, Shuxin, Guo, Dong, Liu, Lifeng
• Format: Journal Article
• Language: English
• Published: Japan The Japanese Society of Internal Medicine 15.01.2020; Japan Science and Technology Agency
• Subjects: Adrenal Cortex Hormones - therapeutic use; anti-leucine-rich glioma inactivated-1 encephalitis; Autoantibodies - immunology; Autoimmune diseases; Case Report; Coexistence; Corticosteroids; Encephalitis; Encephalitis - complications; Encephalitis - drug therapy; essential thrombocythemia; faciobrachial dystonic seizures; Glioma; Glioma - complications; Hashimoto Disease - complications; Hashimoto Disease - drug therapy; Humans; Hydroxyurea; Hyponatremia; Hyponatremia - etiology; Internal medicine; Intracellular Signaling Peptides and Proteins - antagonists & inhibitors; Leucine; LGI1 protein; Limbic Encephalitis - complications; Limbic Encephalitis - drug therapy; Male; Middle Aged; Mycophenolate mofetil; Mycophenolic acid; myeloproliferative neoplasms; paraneoplastic syndrome; Seizures; Seizures - etiology; Short term memory; Thrombocythemia, Essential - complications; Thrombocythemia, Essential - drug therapy; myeloproliferative neoplasms; essential thrombocythemia; faciobrachial dystonic seizures; anti-leucine-rich glioma inactivated-1 encephalitis; paraneoplastic syndrome
• ISSN: 0918-2918; 1349-7235
• DOI: 10.2169/internalmedicine.2963-19

Anti-leucine-rich glioma inactivated-1 (anti-LGI1) encephalitis is a subgroup of autoimmune encephalitis. We herein report the case of a 60-year-old man who presented with typical symptoms, including short-term memory loss, mental abnormalities, hyponatremia and seizures characterized by faciobrachial dystonic seizures and who was diagnosed with anti-LGI1 encephalitis. At the same time, he was diagnosed with essential thrombocythemia. A significant improvement was obtained by treatment with corticosteroid, immunoglobulin, mycophenolate mofetil, and hydroxyurea. Autoimmune diseases are associated with a significantly increased risk of developing myeloproliferative neoplasms, which may explain the coexistence of anti-LGI1 encephalitis and essential thrombocythema in this patient; however, but more cases and studies are needed to determine whether there is any correlation between these conditions.