Résumé
Objective:To summarize the characteristics of clinical, muscle pathology and gene mutation of late-onset reducing body myopathy caused by FHL1 gene mutation, in order to improve clinicians′ understanding of this disorder. Methods:The clinical, muscle pathology and muscle magnetic resonance imaging data of the proband from a family diagnosed as reducing body myopathy in Jiaozuo People′s Hospital in December 2021 were collected. Genetic tests and pedigree verification were conducted on the proband and her son.Results:The proband was a 59-year-old female with progressive, asymmetrical limb weakness and muscular atrophy. Her mother, sister and brother had similar symptoms. Electromyography showed myogenic and neurogenic damage. Muscle magnetic resonance imaging indicated that the lesion mainly involved the posterior muscles of the thigh and calf, as well as the gluteus maximus. The muscle pathology showed eosinophilic granular inclusion bodies and rimmed vacuoles in the muscle fibers of the lesion. The structure of myofibrils was disordered and abnormal protein deposition was observed. The gene sequencing showed the FHL1 gene p.C150S heterozygous variation. Conclusions:Late-onset reducing body myopathy is characterized by progressive asymmetric proximal limb muscle weakness, partially involving distal limb muscles and gluteus maximus. Muscle pathology shows the characteristic pathological changes of many kinds of myofibrillar myopathies. FHL1 gene mutation is an important basis for diagnosis.
Résumé
Objective:To investigate the characteristics of clinical, muscle pathology and gene mutation in patients with nemaline myopathy caused by NEB gene mutation.Methods:The clinical and pathological data of patients with nemaline myopathy caused by NEB gene were collected from Neuromuscular Center of Jiaozuo People′s Hospital from January 1997 to January 2020. The next generation sequencing was preformed to detect NEB gene in all patients, and characteristics of gene mutation were analyzed.Results:Among the 11 patients, there were 8 males and 3 females, and 6 of them came from 2 families. The age of seeing a doctor ranged from 11 to 52 years, the age of onset was from 6 to 23 years, and the course of disease ranged from 5 to 35 years. Neurological examination showed that among the 11 patients, 8 patients had high palatal arch and long face. The muscle tone of both upperlimbs was normal, the tendon reflex was depressed, the proximal muscle strength was grade Ⅲ-Ⅴ, and the distal muscle strength was grade Ⅴ. The muscle tone of both lower extremities was reduced and the tendon reflex was absent. The proximal muscle strength was grade Ⅱ-Ⅳ and the distal muscle strength was grade Ⅲ-Ⅴ. No dysphagia or respiratory muscle involvement was found. Muscle biopsies were performed in 7 of the 11 patients, the pathological changes were muscle fibers of different sizes, circular atrophic muscle fibers and compensatory hypertrophic fibers, and occasionally denatured and necrotic muscle fibers were found. Different degrees of rod aggregation could be seen in all the 7 patients. Electron microscopic examination of 5 patients showed that there was rod aggregation between myofibrils, and most of them were located near the Z band, but no intranuclear rod was found. NEB gene was found in all 11 patients, and a total of 9 different mutation sites were detected, including 8 in exon region and 1 in intron region. Among them, c.21522+3A>G was found in 10 cases, c.1623delT was found in 3 cases and c.17611C>T was found in 3 cases. There was 1 case of c.4417C>T, c.2549delA, c.21065dupA, c.3520G>A, c.20943G>A, c.192G>A respectively.Conclusions:The clinical phenotype of nemaline myopathy caused by NEB gene has great heterogeneity. Muscle pathology shows that rod aggregation is an important basis for the diagnosis of this disease. Mutation c.21522+3A>G in intron is the most common mutation in this group of NEB gene. And the novel mutation sites of NEB gene are respectively c.17611C>T, c.2549delA, c.3520G>A, c.21065dupA, c.20943G>A and c.192G>A.
Résumé
Objective:To investigate the clinical characteristics, skeletal muscle pathologies and gene variations of chronic progressive external ophthalmoplegia (CPEO).Methods:Sixteen patients with conformed CPEO, admitted to our hospital from January 1997 to December 2021, were chosen. Their clinical data such as onset age and course of diseases and muscle pathological examination results were collected and their gene variation characteristics were analyzed.Results:The initial symptom in all 16 patients was ptosis of varying degrees; 15 patients were with eye movement disorder, 6 with diplopia, 4 with proximal limb weakness, and 3 with dysphagia and dysarthria. Among the 16 patients, electromyography showed myogenic damage in 7 patients, myogenic combined with neurogenic damage in 1 patient, neurogenic damage in 1 patient, and normal in 7 patients. Skeletal muscle biopsies indicated that 14 patients were with ragged red fibers (RRF), 11 patients had cytochrome C oxidase (COX)-negative muscle fibers, 3 patients had a small amount of degenerated and necrotic myofibers with mononuclear phagocytic infiltration. Immunohistochemical staining indicated infiltration of CD8 and CD68 positive lymphocytes. Ten patients accepted genetic test, indicating 6 patients with single large fragment deletion of mitochondrial DNA (mtDNA), 1 patient with mtDNA point mutation, 1 patient with nucleosomal DNA (nDNA) point mutation, and 2 patients without pathogenicity variation clearly associated with clinical phenotype. Electron microscopy in 5 patients showed that abnormal mitochondrial aggregation was noted in 4 patients under the sarcolemma and among the myofibrils.Conclusion:In addition to ptosis and eye movement disorders, a small number of patients with CPEO may be accompanied by dysphagia and limb weakness; and single large fragment deletion of mtDNA is the main mutation form of CPEO.
Résumé
Objective:To investigate the clinical characteristics, skeletal muscle pathologies and gene variations of chronic progressive external ophthalmoplegia (CPEO).Methods:Sixteen patients with conformed CPEO, admitted to our hospital from January 1997 to December 2021, were chosen. Their clinical data such as onset age and course of diseases and muscle pathological examination results were collected and their gene variation characteristics were analyzed.Results:The initial symptom in all 16 patients was ptosis of varying degrees; 15 patients were with eye movement disorder, 6 with diplopia, 4 with proximal limb weakness, and 3 with dysphagia and dysarthria. Among the 16 patients, electromyography showed myogenic damage in 7 patients, myogenic combined with neurogenic damage in 1 patient, neurogenic damage in 1 patient, and normal in 7 patients. Skeletal muscle biopsies indicated that 14 patients were with ragged red fibers (RRF), 11 patients had cytochrome C oxidase (COX)-negative muscle fibers, 3 patients had a small amount of degenerated and necrotic myofibers with mononuclear phagocytic infiltration. Immunohistochemical staining indicated infiltration of CD8 and CD68 positive lymphocytes. Ten patients accepted genetic test, indicating 6 patients with single large fragment deletion of mitochondrial DNA (mtDNA), 1 patient with mtDNA point mutation, 1 patient with nucleosomal DNA (nDNA) point mutation, and 2 patients without pathogenicity variation clearly associated with clinical phenotype. Electron microscopy in 5 patients showed that abnormal mitochondrial aggregation was noted in 4 patients under the sarcolemma and among the myofibrils.Conclusion:In addition to ptosis and eye movement disorders, a small number of patients with CPEO may be accompanied by dysphagia and limb weakness; and single large fragment deletion of mtDNA is the main mutation form of CPEO.