Clinical Analysis Of Anti-LGI1 Antibody-related Encephalitis And Literature Review

Background:The clinical manifestations of anti-leucine-glioma inactivation 1 protein（LGI1）related encephalitis are complex and diverse,and symptoms such as cognitive impairment,mental behavior abnormalities,involuntary movements,and atypical seizures can occur at different stages of the disease,and it is easy to be ignored or even misdiagnosed by clinicians in the early stages of the disease.Many patients with antiLGI1 antibody-associated encephalitis present in the early stages of the disease,but immunotherapy in the early stages of the disease can delay or even avoid the progression of cognitive impairment.Early identification and diagnosis of the disease is therefore essential.Objective:Combined with relevant literature at home and abroad,the clinical analysis of 4patients with anti-LGI1 antibody-related encephalitis recently confirmed was carried out,and the possible pathogenesis,clinical manifestations,auxiliary examinations,treatment plan and prognosis of anti-LGI1 antibody-related encephalitis were summarized to improve the understanding of the disease.Methods:From May 2020 to November 2021,patients with suspicious diagnosis of autoimmune encephalitis admitted to the Department of Neurology of our hospital were collected and sent for autoimmune antibodies,and 4 cases of positive serum and/or cerebrospinal fluid anti-LGI1 antibodies were screened from them,and case review analysis and follow-up were carried out.The basic information and clinical data of 4patients diagnosed with anti-LGI1 antibody-related encephalitis were analyzed by professional neurologists,and the basic information of the cases included: gender,age,past history,family history,etc.;clinical data included: onset cause,form of onset,clinical manifestations,positive auxiliary examination results,treatment plan and prognosis.Collate and summarize the clinical characteristics of the case.Results:1.General situation: among the 4 patients,the ratio of men and women is 1:1,and the average age of onset is 57 years old;the previous history of the patient in Case 1,the previous history of the patient in Case 2 has no special history,the patient in Case3 has a history of hypertension,the diabetes is diagnosed after admission,the previous diabetes history of the patient in Case 4 is not special;the family history of the 4 patients is not special.2.Clinical features: the first patient,a 63-year-old female,was admitted to the hospital mainly due to "cognitive decline for 1 month,left upper limb involuntary twitching for 3 days",and the typical facial-brachial dystonic seizures（FBDS）occurred during the course of the disease;the second patient,a 56-year-old female,mainly admitted to the hospital for "episodic visual and hearing impairment for 10 months,cognitive function loss for 1 month",highlighting the clinical manifestations of severe near-memory loss,The course of the disease was accompanied by visual and auditory abnormalities and seizures and other symptoms;the third patient,a 44-year-old man,was admitted to the hospital with "17 months of loss of narcolepsy consciousness and1 month of convulsions of the left lower limb",and symptoms such as personality changes and seizure tone of the left lower limb appeared during the course of the disease;the fourth patient,a 56-year-old man,mainly admitted to the hospital for "memory loss for more than 1 month,aggravation with confusion of consciousness for 1 day",with cognitive impairment as the prominent manifestation,and symptoms such as epileptic seizures,local small seizures,and hallucinations appeared during the course of the disease.Patients in examples 1,2,and 4 develop hyponatremia.In case 2-4,serum and cerebrospinal fluid anti-LGI1 antibodies were positive,and patients in case 1 were positive for serum anti-LGI1 antibodies and negative for cerebrospinal fluid.Among them,patients 1,2 and 4 had limbic system changes in head MRI,examples 1 and 2were bilateral hippocampus,and case 4 was bilateral temporal lobe and hippocampus.In case 3,no specific manifestations of head MRI were seen.EEG in all four patients showed abnormalities.All four patients were screened for tumors without abnormalities.3.Treatment plan and prognosis: Immunoglobulin and high-dose hormone shock therapy are given after the diagnosis is clearly diagnosed in Case 1,3 and 4,immunoglobulin and conventional hormone therapy are given after the initial diagnosis of the patient in Case 2,and immunoglobulin and high-dose hormone shock are repeatedly given after 2 months of regular taking of hormones.Patients 1 and 3 had symptoms remission and no significant neurologic symptoms;Patient 2 had partial remission and left memory loss;Patient 4 had mild cognitive decline.Both are under further recovery.Conclusion:1.The incidence of anti-LGI1 antibody-related encephalitis is low,mainly manifested as typical limbic encephalitis（LE）symptoms,of which seizure forms are diverse,and the seizure forms are different at different stages of the disease course,which requires special attention;2.Serum and / or cerebrospinal fluid anti-LGI1 antibody positive for the anti-LGI1 antibody related encephalitis diagnosis gold standard,for suspected anti-LGI1 encephalitis patients should be tested,immunotherapy responds well to it,early immunotherapy can delay,prevent disease progression,promote disease recovery.