Anti-leucine-rich glioma inactivated-1 autoimmune encephalitis: A review of diagnosis and treatment

Anti-leucine-rich glioma inactivated-1 (LGI1) autoimmune encephalitis is the second most common autoimmune encephalitis, usually with acute or subacute onset. The rates of misdiagnosis and missed diagnosis are high because of its insidious onset. We review the pathogenesis, clinical manifestations, differential diagnosis, treatment, and prognosis of anti-LGI1 autoimmune encephalitis, so as to provide references for clinicians to understand this disease. This disease presents with a variety of clinical manifestations, including faciobrachial dystonic seizure (FBDS), cognitive impairment, hyponatremia, hyperkinetic movements (HMs), and mental impairment. 18F-fluorodeoxyglucose position emission tomography (18F-FDG PET) has higher sensitivity than magnetic resonance imaging (MRI) and can be used to measure disease activity and assess patient response to treatment. The detection of LGI1 antibodies in cerebrospinal fluid or serum is a confirmatory test. The rapid initiation of immunotherapy after diagnosis can significantly improve the prognosis of patients.
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