Anti-MA2 autoinmune encephalitis: A unique case report and narrative concise review

Anti-Ma-2 encephalitis is a rare autoimmune condition which can display a wide range of neuropsychiatric symptoms. It is usually paraneoplastic as 96% of the cases are linked to the presence of a tumor, mainly testicular or pulmonary. Many of these patients can usually be misdiagnosed psychiatrically months before the proper diagnosis is set. Diagnostic battery tests must be exhaustive and treatment includes several lines of medications and treatment of the primary tumor, which determines severe but better prognosis than the rest of autoimmune encephalitic processes. Herein, we present a paradigmatic and almost unique clinical case of a 51-year-old man who was affected of this condition, suffering from left hemichorea, cerebellar and limbic symptoms. The symptomatology had been refractory to several treatment lines and no hidden tumor was detected. The case is accompanied by a narrative concise review of this condition. The wide range of symptomatology displayed, often preceding tumor diagnosis and its severe prognosis make essential to suspect these autoimmune entities when facing neuropsychiatric unusual and complex clinical pictures. Only two previous cases of Anti-Ma 2 encephalitis have been described before with these clinical manifestations, one in Iran and the other one in Germany.