Abstract

Autoimmune encephalitis (AE) is a potentially reversible but often missed cause of acute neuropsychiatric deterioration. It presents a diagnostic challenge for emergency physicians due to its nonspecific early symptoms that resemble infectious, metabolic, or psychiatric disorders. We report the case of a 50-yearold woman who presented to the Emergency Department with acute confusion, aggressive behavior, and memory loss without fever or focal neurological signs. MRI revealed bilateral medial temporal lobe hyperintensities consistent with limbic encephalitis, and cerebrospinal fluid analysis confirmed the presence of antiNMDA receptor antibodies. Based on these findings, a diagnosis of autoimmune encephalitis was established. The patient was managed with high-dose intravenous corticosteroids followed by intravenous immunoglobulins, resulting in rapid clinical recovery and discharge within 10 days. This case highlights the pivotal role of emergency physicians in recognizing autoimmune encephalitis early, initiating prompt immunotherapy, and coordinating multidisciplinary care. Early treatment can prevent irreversible neurological damage, seizures, or progression to coma. Awareness of AE as a differential diagnosis in adults presenting with acute behavioral changes or unexplained altered mental status is essential for improving patient outcomes, especially in resource-limited settings where antibody testing may be delayed.

• 1.   Dalmau J., Lancaster E., Martinez-Hernandez E., Rosenfeld M.R., Balice-Gordon R. Clinical experience and laboratory investigations in patients with anti-NMDAR encephalitis. Lancet Neurol. 2011; 10(1): 63–74.
• 2.   Graus F., Titulaer M.J., Balu R., et al. A clinical approach to diagnosis of autoimmune encephalitis. Lancet Neurol. 2016; 15(4): 391404.
• 3.   Zuliani L., Graus F., Giometto B., Bien C.G., incent A. CNS neuronal surface antibodyassociated syndromes: review and guidelines for recognition. J Neurol Neurosurg Psychiatry. 2012; 83(6): 638–645.
• 4.   Titulaer M.J., Soffietti R., Dalmau J., et al. Treatment and prognostic implications of antiNMDA receptor encephalitis. Lancet Neurol. 2013; 12(2): 157–165.
• 5.   Hainmueller T., Lewis L., Furer T. Anti N-methyl-D-aspartate autoimmune encephalitis following COVID-19 infection. Front Neurol. 2023; 14: 10725953.
• 6.   Leypoldt F., Wandinger K.P., Bien C.G. Autoimmune encephalitis: recent clinical and biological advances. J Neurol. 2023; 270(12): 7095–7112.
• 7.   Chien C.Y., Chang C.Y., Yu W.W. Autoimmune encephalitis: what the radiologist needs to know. Neuroradiology. 2024; 66(8): 1197–1208.
• 8.   Binks S.N., Nicholson T.R., Lagrange L. Outcome and sequelae of autoimmune encephalitis. J Clin Neurosci. 2023; 106: 313–320.
• 9.   Irani S.R., Michell A., Lang B., et al. Precision assessment of anti-NMDAR receptor encephalitis. Cell Death Dis. 2024; 15(5): 518.
• 10.   Orbach D.B., Pillai S.K., Ketenci S. Autoimmune encephalitis misdiagnosis in adults. JAMA Neurol. 2022; 79(7): 644–652.

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