Analysis Of Clinical Features Of Neuronal Surface Antibody Associated Autoimmune Encephalitis

Objective:To investigate the clinical features of different types of neuronal surface antibodyassociated autoimmune encephalitis(AE).Methods:The clinical data of neuronal surface antibody associated AE patients diagnosed in the First Affiliated Hospital of Da Lian Medical University from January2013 to June 2019 were collected,and those patients’demographic data,clinical symptoms,electroencephalogram(EEG),imaging,laboratory examination,treatment and prognosis information were analyzed retrospectively.Results:A total of 18 cases of neuronal surface antibody associated AE were collected,including 9 cases of anti-leucine-rich glioma inactivated 1 protein(LGI1)antibody associated encephalitis and 7 cases of anti-N-methyl-D-aspartate receptor(NMDAR)encephalitis,2 cases of anti-γ-aminobutyric acid B receptor(GABA_BR)encephalitis.The clinical symptoms of the patients were seizures,mental and behavioral abnormalities and cognitive dysfunction.All 9 cases with LGI1encephalitis had seizures,including 4 faciobranchial dystonia seizure(FBDS),6mesial temporal lobe epilepsy(MTLE)-like seizure and 7 focal to bilateral tonic–clonic seizure(FBTCS).Six of 9 cases(66%)showed abnormalities in brain MRI,among them 4 showed high T2/flair signal on unilateral/bilateral hippocampus,2 showed high T1/T2 signal on unilateral basal ganglia.All 9 patients showed abnormalities in EEG.7 patients were accompanied by hyponatremia.Eight patients received immunotherapy,1 was only treated with antiepileptic drugs.Eight patients improved significantly with seizure free after immunotherapy,only 1 still had FBDS after immunotherapy and AED treatment.During the follow-up period,2 patients were lost,and none of the 7 followed up patients developed a recurrence.Among 7patients with NMDAR encephalitis,4 had mental disorders and 5 had seizures.Three cases showed abnormality in MRI,1 showed abnormal signal on hippocampus and 2showed abnormal signal on cortex.All 7 patients showed abnormalities in EEG.All 7patients were treated with immunotherapy and the clinical symptoms improved significantly after immunotherapy.Six of the 7 patients had no recurrence during follow-up,and 1 relapsed 25 months after discharge.Two patients with anti-GABA_BR encephalitis all had seizures as the first symptom.All 2 had generalized tonic-spastic seizures,and one of them had a status epilepticus.One case showed abnormal signals on the left hippocampus in MRI.All showed abnormalities in EEG,one show slow wave activity in the left temporal lobe andone showedfocal slow wave activity.Both patients had lung cancer.The symptoms of 2 patients improved after immunotherapy.One patient died of lung cancer 6 months after discharge.One patient had no seizures or mental abnormalities at the last follow-up.Conclusion:The clinical symptoms of neuronal surface antibody associated AE mainly manifest as mental behavior abnormalities,seizures,and cognitive dysfunction.FBDS is a specific clinical manifestation of LGI1 encephalitis,and LGI1 encephalitis usually affects hippocampus and basal ganglia of the brain.MRI can help detect lesions,and patients are often accompanied by hyponatremia.As NMDAR encephalitis,psychiatric symptoms are more common in adults and can be the first symptom.Frontalδactivity may be a specific EEG pattern.Patients with GABA_BR encephalitis often have Status epilepticus and are more likely to have lung cancer.Detection of specific antibodies in cerebrospinal fluid can clearly diagnose neuronal surface antibodyassociated AE.Anti-epileptic drugs can help control seizures.For patients with tumors,they should actively treat tumors.