一位19歲女性以發燒、全身僵硬、意識障礙為表現之病例報告

抗NMDA（N-methyl-D-aspartate）受體腦炎是當人體自身免疫系統產生的抗體攻擊大腦中的NMDA型谷氨酸受體所導致的自體免疫腦炎。發病初期會出現精神症狀，常沒有神經影像學，腦波或腦脊髓液檢查的異常。它很容易被誤診為原發性精神疾病或其他疾病，像是抗精神病藥物惡性症候群（Neuroleptic maligmant syndrome,NMS）、病毒性腦炎、惡性緊張症、藥物濫用、裝病等。抗NMDA受體腦炎症狀與NMS幾乎完全相似不容易被鑑別診斷。自2007年開始因免疫醫學的進步，才終於可以被明確診斷，在此之前有許多病人因為沒有被診斷出抗NMDA受體腦炎而終身被當成精神病人。本案例詳述一位19歲年輕女性出現急性精神異常症狀，自發病、治療、到確診為抗NMDA受體腦炎的經過，並探討疾病的經過、治療的反應及診斷的困難。  Anti N-methyl-D-aspartate antibody encephalitis (Anti-NMDA antibody encephalitis) develops when such antibody binds and damages NMDA receptors in the brain. Psychiatric symptoms and signs,such as hallucination, acute psychosis and delusional state, are often found as early clinical presentations,rather than brain lesion that can be found on neuroimaging. The CSF and EEG studies are often normal, thus such cases are easily misdiagnosed as acute psychosis, neuroleptic malignant syndrome (NMS), viral encephalitis, substance abuse, or malingering. In fact, the symptoms and signs of anti-NMDA antibody encephalitis and NMS are almost identical, making it especially difficult to diagnose. From Since 2007, thanks to the advances of Immunology, such autoimmune encephalitis is now able to be diagnosed accurately. In the past, lots of victims were treated as psychotics when anti-NMDA antibody was not able to be detected. In this case report, we illustrated the clinical presentation, disease progress, responses to treatment, and how the final diagnosis of anti-NMDA encephalitis was made on a 19 years old female who developed acute psychosis.