肢带型肌营养不良

Limb-girdle muscular dystrophy

肢带型肌营养不良(LGMD)是一组临床表现为肢带肌无力及萎缩、具有遗传异质性的肌肉疾病。在国内,LGMD是除迪谢内/贝克型肌营养不良、面肩肱肌营养不良及强直性肌营养不良外,发病率最高的一种肌营养不良。LGMD多在少年或成人起病,常就诊于神经内科。因其表现为四肢近端无力,容易与炎性肌病、代谢性肌病等混淆。最终诊断依赖于肌肉活体组织检查免疫组织化学染色、免疫印迹及基因检测。我国的LGMD2B(dysferlinopathy)及LGMD2A(calpainopathy)约占LGMD总数的74.3%。其中LGMD2B比例最高,多在19~27岁起病,早期可以表现为无症状高肌酸激酶血症,中后期绝大部分患者进展为肢带综合征,伴小腿后群变细及血肌酸激酶水平显著升高。第二常见的是LGMD2A,多在7~18岁起病,以伴或不伴翼状肩/跟腱挛缩的肢带综合征为主要表现,血肌酸激酶水平常升高。目前LGMD尚无有效的治疗手段,但自然史研究及基因治疗临床试验为LGMD患者的治疗带来了新的希望。

Limb girdle muscular dystrophy (LGMD) is characterized by progressive proximal muscle weakness with high genetic heterogeneity. LGMD is the fourth prevalent form of muscular dystrophies in the adult neurology department. Since most patients are juvenile-or adult-onset and present as limb muscle weakness, it would be easily misdiagnosed as myositis or metabolic myopathies. The final diagnosis depends on muscle immunohistochemical staining, Western blotting and genetic screening. In China, LGMD2B and LGMD2A are the most prevalent forms, accounting for 74.3% in overall LGMD. Patients with LGMD2B usually have onset age between 19-27 years old. LGMD2B patients present as asymptomatic hyper creatine kinase emia (CK) at the early stage, and later develop to typical proximal muscle weakness with bilateral calf atrophy and extremely high serum CK. The onset age of LGMD2A patients is between 7-18 years old. LGMD2A patients presented as proximal muscle weakness with or without bilateral scapular winging and Achilles tendon contractures. Serum CK can be moderately or highly elevated. Current therapies are mainly supportive and the effective treatment is insufficient. The ongoing global clinical history study and gene therapy bring us new hope for treating LGMD in the coming future.