Dystrophic muscle distribution in late-stage muscular dystrophy

There is scant information about the comprehensive distribution of dystrophic muscles in muscular dystrophy. Despite different clinical presentations of muscular dystrophy, a recent multi-center study concluded that phenotypic distribution of dystrophic muscles is independent of clinical phenotype and suggested that there is a common pattern of involved muscles. To evaluate this possibility, the present case report used cadaveric dissection to determine the whole-body distribution of fat-infiltrated, dystrophic muscles from a 72-year-old white male cadaver with adult-onset, late-stage muscular dystrophy. Severely dystrophic muscles occupied the pectoral, gluteal and pelvic regions, as well as the arm, thigh and posterior leg. In contrast, muscles of the head, neck, hands and feet largely appeared unaffected. Histopathology and a CT-scan supported these observations. This pattern of dystrophic muscles generally conformed with that described in the multi-center study, and provides prognostic insight for patients and the physicians treating them.

Limb-girdle muscular dystrophy / 中华神经科杂志

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 elinical history study and gene therapy bring us new hope for treating LGMD in the coming future.

Clinical and pathological features of the 5 Limb-girdle muscular dystrophy 2A patients / 中华神经科杂志

Objective To investigate the clinical and molecular pathological features of limb-girdle muscular dystrophy 2A (LGMD2A) of Chinese patients. Methods Thirty cases of LGMD with excluding LGMD2B were included in this study. The muscle specimens were performed by a standard series methods of histochemistry, enzymohistochemistry, immunohistochemistry and Western blot. The clinical and molecular pathological features of LGMD2A were retrospective analyzed. Results Five cases with no or only trace expression of calpain-3 protein were diagnosed as calpainopathy (LGMD2A) by Western blot analysis. The age of onset of these 5 patients ranged from 10 to 45 years and the duration of the disease were about 2-10 years. Proximal muscles weakness and atrophy of lower limbs were predominantly involved. In all patients,symptoms progressed slowly. The ambulation could be retained for many years but running and jumping were impaired early. The serum creatine kinase level was elevated moderately to markedly. Electromyography showed myopathic patterns in all cases. Two siblings had similar symptoms indicating autosomai recessive inherited pattern. Pathologically, there was marked variation in fibre size and most small fibres were round. Some necrotic and regenerating fibers were seen. Fibres with centrally placed nuclei can be found frequently. No infiltrations of inflammatory cells were seen. Lobulated fibers were observed in 2 patients by NADH-TR stain. The expression of dystrophin, caveolin-3, α-, β-, γ- and δ-sarcoglycan protein were normally staining of 5 LGMD2A patients' specimens by immunohistochemistry. Two patients had reduced staining of dysferlin by immunohistochemistry study. Conclusions Clinical and pathological characteristics of our 5 LGMD2A patients are consistent with typical muscular dystrophy features reported in other countries. Identification of calpian-3 deletion by Western blot is essential for the diagnosis of calpainopathy.