A Prospective Study to Evaluate Clinical Outcomes in Anti-LGI1 Encephalitis

Study Overview
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Brief Summary
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Anti-leucine-rich glioma-inactivated 1 (LGI1) encephalitis has been increasingly identified as the second most common type of autoimmune encephalitis after anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. It presents with acute or subacute onset of epileptic seizures, anterograde amnesia, behavior disturbances, sleep disorders and hyponatremia. In most patients with anti-LGI1 encephalitis, immunotherapy is successful in treating the encephalitis. However, relapses, chronic epilepsy, cognitive declines and psychiatric problems have been reported in some cases. So far, prospective studies to evaluate its clinical outcomes still remain limited. In this project, the investigators will use clinical features and advanced paraclinical examinations to prospectively investigate the clinical outcomes and the associated factors in patients with anti-LGI1 encephalitis.

Detailed Description
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In this prospective study, the investigators are aiming to recruit newly diagnosed patients with anti-LGI1 encephalitis. At the acute stage and during the follow-up, some routine and advanced paraclinical examinations will be conducted, including dynamic blood and/or cerebrospinal fluid (CSF) test, multimodal brain magnetic resonance imaging (MRI) including functional MRI, diffusion tensor imaging, arterial spin labeling, et al), Electroencephalography (EEG) or continuous video-EEG (VEEG), positron emission tomography (PET), neuropsychological tests and some other paraclinical examinations. Through the comprehensive analysis, the clinical outcomes and associated factors are further explored in anti-LGI1 encephalitis.

Official Title
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A Prospective Study to Evaluate Clinical Outcomes in Patients With Anti-leucine-rich Glioma-inactivated 1 Encephalitis

Conditions
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Autoimmune Encephalitis, Leucine-Rich Glioma Inactivated 1 Autoimmune Encephalitis

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Meet the 2016 consensus diagnostic criteria for anti-LGI1 encephalitis. Newly diagnosed, and during the acute stage before study enrollment. Sign the informed consent form. Exclusion Criteria: with the diagnosis of epilepsy, stroke, cerebral trauma, and/or other nervous system disease prior to the onset of encephalitis. with coexisting antibodies, such as anti-contactin-associated protein 2 (CASPR2) antibody. Lost to follow-up.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 100 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| seizure outcomes | The incidence of different seizure outcomes and associated factors will be analyzed. | 1 year, 2 year | 
| Clinical severity and recovery 1 | modified Rankin scale, ranging from 0-6, higher scores mean a worse outcome | 1 year, 2 year | 
| Clinical severity and recovery 2 | clinical assessment scale for autoimmune encephalitis, ranging from 0-27, higher scores mean a worse outcome | 1 year, 2 year | 
| Incidence of recurrence | a relapse of encephalitis | 1 year, 2 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Memory assessment 1 | the Wechsler Memory Scale, high score means a good memory. | 1 year, 2 year | 
| Memory assessment 2 | Rey Auditory Verbal Learning Test (RAVLT), high score means a good vebal episodic memory. | 1 year, 2 year | 
| Brain volume | with 3T magnetic resonance imaging (MRI), volumes of the whole hippocampus, hippocampal subfields and other relevant regions were determined using FreeSurfer. The unit of volume is described as mm3. | 1 year, 2 year |