Comprehensive Analysis Of Genotype,Muscle Pathological Characteristics And Clinical Phenotype Of Hereditary Myopathies In Children

Obiective:The genotype,muscle pathological characteristics and clinical phenotype of children with hereditary myopathies were retrospectively analyzed,so as to improve the ability of diagnosis and differential diagnosis of such diseases and achieve early diagnosis and timely treatment.Methods:We screened 75 cases of children with hereditary myopathies diagnosed by muscle biopsy and/or gene test in pediatric department of our hospital from January 2014 to December 2018,with retrospective analysis of these children with history,laboratory examinations,muscle pathology and related genetic testing results.Follow-ups were conducted to understand the changes and current situation of children,and relevant literatures were reviewed.Results:According to the statistics,75 cases of hereditary myopathies in children were involved in 9 types of diseases:63 cases of muscular dystrophy(84%),among which 57 cases of dystrophinopathy(76%),2 cases of limb-girdle muscular dystrophy(2.7%)and 4 cases of congenital muscular dystrophy(5.3%);3 cases(4%)of congenital myopathy,including 2 cases(2.7%)of nemaline myopathy and 1 case(1.3%)of congenital fiber type disproportion;7 cases(9.3%)of metabolic myopathy,including 2 cases(2.7%)of lipid storage myopathy and 5 cases(6.7%)of mitochondrial encephalomyopathy;1 case of distal myopathy(1.3%);1 case of ion channel disease.Among 75 cases,60 cases underwent muscle pathological examination with 56 cases confirmed;50 cases underwent gene testing with 48 cases confirmed.1 case was confirmed by comprehensive analysis.Gene variations of dystrophinopathy occurred frequently in exon 44-55 of DMD gene.Conclusions:Muscular dystrophy and mitochondrial encephalomyopathy are common in children with hereditary myopathies in our hospital.Children with hereditary myopathies have a variety of clinical symptoms.In addition to manifestations of muscle,Initial symptoms include other systemic nonspecific manifestations or no symptoms at all.Attention to other systemic complications and prompt symptomatic treatment.The diagnosis of hereditary myopathies requires a comprehensive analysis of clinical,biochemical,electrophysiological,muscle pathology and genetic testing,among which muscle biopsy and genetic testing are the most important methods for diagnosis.The definite diagnosis must be distinguished from neurogenic diseases and neuromuscular junction diseases.