The Clinical Research Of Neuromuscular Junction Antibody And Myasthenia Gravis

Objective:To describe the expression of different types of serum neuromuscular junction(NMJ)antibodies in myasthenia gravis(MG)patients,and compare the clinical characteristics of patients with different types of MG.Methods:A retrospective analysis of the clinical data of 83 patients who were hospitalized in the Department of Neurology,the First Affiliated Hospital of Xinjiang Medical University from January 2018 to November2020,was clearly diagnosed as MG and completed the serum NMJ antibody test.The MG patients were grouped according to their serum antibody expression,clinical classification,and age of onset.Compare its clinical manifestations,laboratory tests and serum NMJ antibody expression.Among them,acetylcholine receptor antibody(Ach R-Ab),Muscle-sepecific receptor tyrosine kniase antibody(Musk-Ab),voltage-gated calcium channel(VGCC)antibody were determined by radioimmunoprecipitation assay(RIA),the anti-Titin antibody(Titin-Ab)was measured by enzyme linked immunosorbent assay(ELISA),and low-density lipoprotein receptor-related protein4(LRP4)antibody was measured by transfected cells.Results:Among 83 MG patients,32 were males and 51 were females.There was no significant difference in the age of onset of MG between different genders.The positive rates of serum Ach R-Ab,Titin-Ab and Musk-Ab in MG patients were 77.1%,32.5%,2.4%,respectively.Ach R-Ab positive patients had a higher EMG RNS positive rate than negative MG patients,and the difference was statistically significant(P<0.01).Titin-Ab was more common in the serum of LOMG patients,and was easily combined with Ach R-Ab positive,and the positive rate of electrophysiological examination was also high,with statistically significant diffrerence(P<0.01).The positive rate of Mus K-Ab was low,the age of onset was earlier,and the thymus was generally not accumulated.Conclusion:The NMJ antibody with the highest positive rate in the sera of MG patients was Ach R-Ab,which was often combined with Titin-Ab double positive.Compared with pure Ach R-Ab-positive MG patients,the latter has a more severe condition,mainly systemic symptoms,and was prone to thymic hyperplasia/ thymoma.Mus K-Ab generally appears in patients with serum Ach R-Ab negative MG(SNMG),the positive rate is10.5%(2/19),and the condition is serious.