myotubular myopathy


myopathy

 [mi-op´ah-the] any disease of a muscle. adj., adj myopath´ic.centronuclear myopathy myotubular myopathy.distal myopathy an autosomal dominant form of muscular dystrophy, appearing in two types. The first has onset in infancy, does not progress past adolescence, and is not incapacitating. The second has onset in adulthood and is called myopathy" >late distal hereditary myopathy. Called also distal muscular dystrophy.glycolytic myopathy any myopathy" >metabolic myopathy resulting from a defect of glycolytic enzyme activity, marked by exercise intolerance and cramping, the accumulation of glycogen in muscle, and recurrent myoglobinuria.late distal hereditary myopathy myopathy" >distal myopathy that sets in usually after age 40, does not affect life span and first affects the small muscles of the hands and feet and then spreads proximally.metabolic myopathy myopathy due to disordered metabolism, usually caused by genetic defects or hormonal dysfunction.mitochondrial myopathy any of a group of myopathies associated with an increased number of enlarged, often abnormal, mitochondria in muscle fibers, manifested by exercise intolerance, generalized weakness, acidosis" >lactic acidosis, infantile tetraparesis, ophthalmoplegia, and cardiac abnormalities.myotubular myopathy a form marked by myofibers resembling the myotubules" >myotubules of early fetal muscle.nemaline myopathy a congenital abnormality of myofibrils in which small threadlike fibers are scattered through the muscle fibers; marked by hypotonia and proximal muscle weakness.ocular myopathy a slowly progressive form affecting the extraocular muscles, with ptosis and progressive immobility of the eyes.

cen·tro·nu·cle·ar my·op·a·thy

slowly progressive generalized muscle weakness and atrophy beginning in childhood; on biopsy of skeletal muscle, the nuclei of most muscle fibers are seen to be located near the center of a small fiber (the normal position for a 10-week embryo) rather than at the periphery of the fiber; familial incidence. Autosomal dominant [MIM*160150] recessive [MIM*255200] and X-linked [310400] forms occur. The X-linked form is caused by mutation in the myotubular myopathy gene (MTM1) on Xq28. Synonym(s): myotubular myopathy

myotubular myopathy

Centronuclear myopathy A myopathy with various patterns of inheritance; all have centrally-located nuclei in muscle fibers, surrounded by cytoplasmic material with features of maturing myotubules, accompanied by atrophy of type I and hypertrophy of type II muscle fibers; the X-linked form results in neonatal death due to respiratory muscle insufficiency; the AD form is benign. See Myopathy.