The Clinical Characteristics And Prognosis Of Seizures In Autoimmune Encephalitis

Background and ObjectiveSince the anti-N-methy-D-aspartate receptor(NMDAR)encephalitis was discovered and named in 2007,a number of people have known about autoimmune encephalitis(AE)when a series of new antibodies had been found.Anti-NMDAR,anti-leucine-rich glioma inactivated 1(LGI1),anti-?-amino-butyric acid-B receptor(GABABR)and anti-contactin associated protein-like 2(Caspr2)are the common cell surface antibodies.The intracellular antibodies include anti-Hu,anti-GAD,anti-CV2/CRMP5 and so on.Patients with AE typically present with behavioral dysfunction,cognitive impairment,autonomic instability and seizures.Seizures can occur at any stage in AE,some patients develop to status epilepticus,or even super-refractory status epilepticus.A part of researches indicate that AE has became an important reason in secondary epilepsy.Some studies have found that seizures are common in AE,but most patients have a good prognosis after AE was cured,and they rarely develop epilepsy.At present,there are several studies on AE-related seizures,and they mainly foucs on anti-NMDAR encephalitis.Hence,this study analyse and conclude the seizure features,the brain magnetic resonance imaging(MRI),electroencephalogram,routine cerebrospinal fluid examinations,treatments and prognosis of patients with AE-related seizures about different antibodies in our hospital,and combine with internal and foreign literatures to analyse the characteristics,treatments and prognosis of seizures in different antibodies,providing the new ideas and methods for clinicians in the management of seizures associated with AE.Materials and MethodsWe analysed clinical characteristics of patients with AE accompanied by seizures in the First Affiliated Hospital of Zhengzhou University between January 2015 to June 2019 retrospectively.Clinical information contain age,gender,the features of seizures,the brain MRI,the routine cerebrospinal fluid examinations,electroencephalogram,the results of screenings for systemic neoplasms and threapy,and the follow-up was conducted by telephone to knew prognosis of seizures in these patients.Results1.In 96 patients with AE(53anti-NMDAR,22anti-LGI1,21 anti-GABABR),72.9%(70/96)had seizures(35anti-NMDAR,17anti-LGI1,18anti-GABABR),and 50%(48/96)exhibited seizures as the initial symptom of AE.2.In these 70 patients who had seizures,the median age at onset of disease was 44 years old,and 57.1%(40/70)were males.88.6%(62/70)had seizures in the first two weeks.18.6%(13/70)exhibited two or more seizure semiology;65.7%(46/70)exhibited generalized tonic-clonic seizure,4.3%(3/70)exhibited typical absence,12.9%(9/70)exhibited focal motor seizure,15.7%(11/70)exhibited focal nonmotor seizure,1.4%(1/70)exhibited focal to bilateral tonic-clonic seizure,and 5.7%(4/70)presented with faciobrachial dystonic seizures.21.4%(15/70)developed to status epilepticus.3.95.7%(67/70)had brain MRI,41.8%(28/67)were found abnormal,and the hippocampus/temporal lobe was more likely to be involved.The all patients had routine cerebrospinal fluid examinations,and the elevation of pressure,white blood cell,lymphocytes and protein levels were found;16 patients underwent electroencephalogram,8 patients were abornomal,7 patients were found diffuse slowing,and the one patient without clinical seizures were found sharp waves during electroencephalogram examinations;69 patients screened for tumor after admission,14.5%(10/69)were found neoplasms,2 patients were found ovarian teratoma,and 8 patients were found lung cancer.4.94.3%(66/70)were given immunotherapy and antiepileptic drugs therapy.We followed up with fifty-eight patients(one paitent was died,seven patients were lost,four patients were not treated).After a median follow-up of 38 months(7-46months),75.9%(44/58)exhibited seizure remission after immunotherapy,24.1%(14/58)developed to persistent seizures.Recurrence of AE was seen in 29.3%(17/58)of patients,seven patients with anti-NMDAR encephalitis had no seizure,just presented with behavioral or cognitive dysfunction,the four cases presented with seizures in five patients with anti-LGI1 encephalitis,and all of five patients with anti-GABABR encephalitis presented with seizures when AE recurred.Conclusion1.Generalized tonic-clonic seizure is the most common seizure semiology in AE.2.The seizures associated with AE have a good prognosis,most patients present with seizure remission after immunotherapy,and there is no need to use antiepileptic therapy for a long time.3.Anti-LGI1 and anti-GABABR encephalitis are more likely to present with seizures when encephalitis recurs.