Clinical,Pathological And Genetic Characteristics' Study Of Limb-gridle Muscular Dystrophy

Objective:Immunohistochemical staining of dystrophin-associated protein antibodies and gene detection of neuromuscular disease were performed on patients who were initially diagnosed as limb gridle muscular dystrophy by the combination of clinically presented with proximal limb weakness or simple muscle enzyme elevation and muscle tissue routine and enzyme histochemical staining.To improve the awareness of patients with limb-gridle muscular dystrophy and reduce misdiagnosis.Methods:A total of 52 patients who were admitted to the Second Hospital of Hebei Medical University from January 2012 to October 2018 for diagnosis of limb-girdle muscular dystrophy were collected.Their clinical,routine and enzymatic histochemical staining characteristics were summarized.Then immunohistochemical staining of 8 kinds of muscular dystrophy related proteins and detection of neuromuscular disease-related genes(including 234 genes)were performed on 51 patients.Results:1.Summary of clinical dataThere were 52 patients,whose onset age ranged from 3 to 53 years old,and duration of disease ranged from 1 month to 30 years.The main manifestations of 52 patients were proximal limb weakness or simple muscle enzyme elevation.Histopathological findings were normal to severe myogenic changes.2.Immunohistochemical stainingAll the 51 patients underwent immunohistochemical staining.Dysferlin is the most common abnormal protein(45/51,88.2%).Three patients had no abnormalities in muscular dystrophy associated protein.3.Results of genetic testingA total of 122 mutations of 215 genes were detected in 52 cases.35 patients were diagnosed through the combination of clinical and pathological manifestations and genes(67%),including 13 cases(25%)of LGMD2 B,5 cases(9%)of LGMD2 A,1 case(2%)of LGMD2 D,5 cases(9%)of asymptomatic high creatine myosinemia,and 2 cases(4%)of MM myopathy,2 cases(4%)with exercise intolerance,1 case(2%)with near-distal type,4 cases(8%)with BMD,2 cases with immune-mediated necrotic myopathy(anti-SRP antibody positive)(4%));17 patients(33%)were undiagnosed.Conclusion:1.The clinical heterogeneity of muscular dystrophy is large,and the classification is difficult.The final accurate classification requires genetic testing combined with clinical symptoms.2.Limb-gridle muscular dystrophy 2B is most common in China.3.Limb-gridle muscular dystrophy has high genetic heterogeneity.The clinical manifestations of the same gene mutation may be different even in the same family.4.It is difficult to distinguish limb band muscular dystrophy from some muscular dystrophy and inflammatory myopathy in clinical manifestations and pathology,and the diagnosis requires the combination of clinical manifestations,muscle pathology and genes.