emerin and Muscular-Atrophy

A 42-year-old man with a history of two previous coronary embolisms was referred to our hospital. He had been experiencing muscle weakness since he was around 40 years old. He had muscle atrophy of the scapula, upper arm, and lower extremities, and electromyography revealed myogenic changes in the limb muscles. Histopathological analysis of the muscle biopsy specimen revealed a complete deficiency of emerin protein, and genetic examination revealed a mutation in the emerin (EMD) gene, resulting in a diagnosis of Emery-Dreifuss muscular dystrophy (EDMD). EDMD is a muscular disorder with three symptoms: joint contracture at early onset, muscle weakness and atrophy, and cardiac dysfunction. Although this patient showed no obvious joint contracture, the course and clinical symptoms vary among patients. Therefore, in patients in whom clinical diagnosis is difficult, muscle biopsy and genetic testing should be performed for EDMD in order to prevent sudden death due to this disease.

Topics: Adult; Contracture; Humans; Joints; Male; Membrane Proteins; Muscle Weakness; Muscle, Skeletal; Muscular Atrophy; Muscular Dystrophy, Emery-Dreifuss; Mutation; Nuclear Proteins

Emery-Dreifuss muscular dystrophy, caused by EMD gene mutations, is characterized by humeroperoneal muscular dystrophy, joint contractures, and conduction defects and is often associated with sudden cardiac death, even without prior cardiac symptoms.. To describe the clinical and molecular features of 2 patients with limb-girdle muscular dystrophy with mutations in EMD.. Case reports.. Academic research.. Two male patients manifested proximal dominant muscle involvement, with minimal or no joint and cardiac involvement.. Muscle biopsy and mutation analysis results.. Immunohistochemistry revealed an absence of emerin staining in muscle biopsy specimens. Mutation analysis identified nonsense mutations in EMD.. Mutations in EMD may indicate a limb-girdle muscular dystrophy phenotype. Identification of emerin deficiency among patients with limb-girdle muscular dystrophy is essential to prevent cardiac catastrophe.

Topics: Biopsy; Child; Codon, Nonsense; DNA Mutational Analysis; Extremities; Gene Deletion; Genetic Markers; Genetic Predisposition to Disease; Heart Block; Humans; Immunohistochemistry; Male; Membrane Proteins; Middle Aged; Muscle, Skeletal; Muscular Atrophy; Muscular Dystrophies, Limb-Girdle; Mutation; Myocardium; Nuclear Proteins

Hauptmann-Thannhauser muscular dystrophy is characterized by the clinical triad of early-onset contractures of elbow, Achilles tendons, and cervical spine, slowly progressive humeroperoneal muscle wasting and weakness, and life-threatening cardiac involvement with conduction blocks manifesting in the third decade. Hauptmann-Thannhauser muscular dystrophy is due to mutations in the LMNA gene affecting the nuclear envelope proteins lamin A and C. We present a 16-year-old German boy with typical muscular involvement and contractures and typical course of Hauptmann-Thannhauser muscular dystrophy due to the novel missense mutation R401C. The data of this family suggest a lower penetrance of muscular and especially cardiac symptoms than expected. Autosomal-dominant Hauptmann-Thannhauser muscular dystrophy and X-chromosomal Emery-Dreifuss muscular dystrophy are not clearly distinguishable by phenotypic criteria. Other muscular diseases associated with contractures and congenital or childhood onset are reviewed.

Topics: Adolescent; Biopsy; Cardiomyopathies; Cell Nucleus; Contracture; Humans; Lamin Type A; Male; Membrane Proteins; Muscle Weakness; Muscle, Skeletal; Muscular Atrophy; Muscular Dystrophy, Emery-Dreifuss; Mutation, Missense; Neurologic Examination; Nuclear Proteins; Pedigree; Phenotype; Syndrome; Thymopoietins