Muscular Dystrophy
Alfred J. Spiro MD1
1 Albert Einstein College of Medicine, Bronx, NY
Editors: Henry M. Adam, MD.
Several varieties of muscular dystrophy can be distinguished on clinical, genetic, morphologic, and physiologic grounds. The classification includes Duchenne and Becker muscular dystrophies, both X-linked disorders; facioscapulohumeral muscular dystrophy, which is autosomal dominant; and limb-girdle muscular dystrophy, generally autosomal recessive.
Duchenne muscular dystrophy (DMD), which occurs in approximately 1 in 3500 live male births, has no recognizable signs or symptoms at birth. However, markedly elevated serum creatine kinase always is demonstrable, even at birth. A molecular diagnosis can be made at any time in the patient's lifetime by demonstrating the defect in the dystrophin gene, the absence of dystrophin in a muscle biopsy, and the characteristic morphologic abnormalities.
