FHL1基因变异致晚发型还原体肌病一家系报道

FHL1 gene mutation related late-onset reducing body myopathy in a Chinese family

目的总结FHL1基因变异致晚发型还原体肌病的临床、肌肉病理和基因变异特点,提高临床医师对还原体肌病的认识。方法详细收集2021年12月就诊于焦作市人民医院的1个还原体肌病家系中先证者的临床、肌肉病理和磁共振成像资料,并对先证者和其儿子进行基因检测和家系验证。结果先证者为女性,59岁,临床表现主要为进行性、非对称性肢体无力和肌萎缩。先证者母亲、一姐和一弟有类似症状。先证者肌电图提示肌源性合并神经源性损害。肌肉磁共振成像提示病变主要累及大腿和小腿的后组肌群,臀大肌亦有受累。肌肉病理检查结果显示病变肌纤维内可见嗜伊红颗粒状包涵体和镶边空泡,以及肌原纤维结构紊乱和异常蛋白沉积。基因检测发现患者存在FHL1基因p.C150S杂合变异。结论晚发型还原体肌病以进行性、非对称性肢体近端肌无力为特征,部分可累及肢体远端肌肉和臀大肌。肌肉病理检查可见多种肌原纤维肌病特征性的病理改变,基因检测发现FHL1变异是确诊的重要依据。

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.