Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026827 (hypotonia)
 5,860 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 2-year-old boy with Leber's congenital amaurosis, hypotonia, depressed myotatic reflexes, and delayed motor development had numerous foci of broadened or smeared A bands, loss of distinct I bands, and near-normal Z lines in biopsied muscle. The thick filaments in these lesions appeared misaligned, suggesting an abnormality of the M line or of the structural protein connectin. This unique alteration represents the first described morphologic abnormality of muscle in a patient with Leber's congenital amaurosis.
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PMID:Broad A bands of striated muscle in Leber's congenital amaurosis: a new congenital myopathy? 829 76

We report a second child with broad A band disease. This child differs from the first in having normal vision and no electrophysiological evidence of a congenital retinal dystrophy. Neurological abnormalities at presentation included diffuse hypotonia, developmental delay, and delayed speech development. Histological and preliminary histochemical evaluation of biopsied thigh muscle showed no abnormality. However, 1-micrometer-thick plastic sections and electron microscopy showed numerous foci of broadened A bands accompanied by loss of distinct I bands. The Z lines in these areas were normal except for a fine waviness. Ultrastructurally, the thick filaments in these lesions appeared misaligned. Immunohistochemical reactions for desmin, vimentin, connectin (titin), and 2B myosin showed normal reactivity. An immunohistochemical reaction for fetal myosin showed sparse reacting fibers, which were unremarkable on adjacent sections stained with hematoxylin and eosin. These findings differ from those of other previously described congenital myopathies. Both of our patients have shown good strength and motor development by 5 years of age, suggesting that this ultrastructural abnormality is essentially benign.
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PMID:Broad A band disease: a new benign congenital myopathy. 861 56