Clinical Features Of Myasthenia Gravis With Autoimmune Disease

ObjectiveIn order to help understand the clinical characteristics of myasthenia gravis (MG)with autoimmune disease (AD) and the types of AD that may be associated with MG.MethodsCollect the clinical data of 148 patients who were diagnosed as MG in the First Affiliated Hospital of Zhengzhou University from April 2018 to April 2019,including age of onset,sex,MG antibody spectrum (AChRAb?MuSKAb?TitinAb?LRP4Ab),thymus condition (normal,thymic hyperplasia,thymoma),Osserman classification,thyroid condition (FT3?FT4?TSH?TRAb?TPOAb?TGAb?thyroid color Doppler ultrasound),connective tissue factor.The differences of MG related to different MG antibodies in clinical characteristics included age,sex,incidence of thymus hyperplasia,incidence of thymoma,clinical classification,combined AD (including ATD?other AD) were analyzed.According to the AD species,the cases were divided into MG patient group with autoimmune thyroid disease (ATD),MG patient group with other AD,MG patient group with two ADs and simple MG patient group.The incidence and age distribution of patients in MG group,MG with AD group,MG with other AD group and MG with two AD groups were observed,and compared the difference of incidence between different genders in the simple MG group;compared with patients with simple MG,the clinical characteristics of MG patients with AD,MG patients with ATD and MG patients with other AD were analyzed in age,sex,positive rate of MG antibody,positive rate of AChRAb,thymic hyperplasia,thymoma,clinical classification;at the same time,the clinical characteristics of MG with ATD and MG with other AD,MG with one AD and MG with two ADs were compared in age,sex,positive rate of MG antibody,positive rate of AChRAb,thymic hyperplasia,thymoma,clinical classification.Data analysis was carried out by SPSS22.0,and the mean values of variables in accordance with normal distribution were expressed by mean addition and subtraction standard deviation ((?) ± SD).the comparison between mean numbers was tested by independent sample T test and ANOVA,the test level Q=0.05;the counting data were used ?2 tests to indicate the difference,P<0.05 was considered statistically significant.Results1.Compared with AChRAb positive MG,MuSKAb positive MG had higher proportion of women,systemic classification,normal thymus and no ADs,but there was no differences in age,sex,thymus hyperplasia,incidence of thymoma and clinical classification (P>0.05).2.In MG patients and MG without AD group,there were two peaks age of onset,and the peak age is the same (30-34 years,45-59 years),MG patients with AD had no significant age correlation,gender differences in MG incidence were not found in this study.3.Compared with simple MG patients,the MG patients with AD had earlier ages of onset,more women,lower seropositive rate of MG antibody,and were more common in ocular type,the difference was statistically significant (P<0.05),However,the incidence of thymic hyperplasia and thymoma was similar between the two groups (P>0.05).4.Compared with simple MG patients,the incidence of thymoma were lower in MG patients with ATD,which were more common in women and ocular types(P<0.05);There was no statistical difference in the positive rate of MG antibody between the two groups (P>0.05).5.MG patients with other AD had earlier age of onset than those with simple MG,and more frequently in women.The seropositive rate of MG antibody and thymoma were much lower than those in simple MG group (P<0.05).Between the two groups,there was no significant difference in the incidence of thymus hyperplasia and clinical classification (P>0.05).6.There was no significant difference in the clinical characteristics of MG patients with ATD and other AD,such as age,sex,seropositive rate of MG antibody,Incidence of thymic hyperplasia,thymoma,clinical classification (P>0.05).7.Compared with simple MG patients,MG patients with one or two ADs had earlier onset age,more women and more ocular muscle types,and the difference was statistically significant (P<0.05),the MG patients with one AD had lower seropositive rate of MG antibody,lower thymoma,the difference was statistically significant(P<0.05).The incidence of thymoma in MG patients with two ADs was higher than that in MG patients with one AD,and the ocular type was more common,the difference was statistically significant (P<0.05).Conclusions1.AChRAb positive and MuSKAb positive myasthenia gravis patients showed no significant differences in sex,thymus,clinical type and whether they were associated with autoimmune diseases;2.Patients with early onset age,female,ocular myasthenia gravis are more likely to be associated with autoimmune diseases.Among them,patients without thymoma are more likely to have autoimmune thyroid disease;patients without thymoma and seropositive of MG antibody,are more likely with other autoimmune diseases.3.Patients that myasthenia gravis with an autoimmune disease are less likely to be associated with thymoma;if patients that myasthenia gravis with an autoimmune disease associated with thymoma,it should be alert to the coexistence of other autoimmune diseases.