0000000000142033
AUTHOR
Anna Fidziańska
Neonatal form of nemaline myopathy, muscle immaturity, and a microvascular injury.
An infant with a neonatal form of nemaline myopathy showed ultrastructural features of muscle immaturity. Immaturity was characterized by an abnormal presence of myotubes, as well as cells in clusters within a common basement membrane and a great number of satellite cells adhering to very small muscle fibers. In addition, degenerative changes and a severe microvascular lesion were observed. The pathologic findings in the muscle of this patient were those of neonatal nemaline myopathy complicating severe microvascular injury, possibly induced by an unknown toxic agent. ( J Child Neurol 1990;5:122-126).
Myopathic form of arthrogryposis and microcirculation lesion.
A microvascular lesion characterized by extensive platelet aggregation, thrombosis, vascular damage with hemorrhages was found in the muscle of a 2-month-old boy with a myopathic form of the arthrogryposis syndrome. The lesion morphologically resembled the vascular leakage seen in immunologically mediated tissue injury. A degradative effect of proteases released during platelet and neutrophil aggregation on the muscle and joints is suggested.
ACUTE INFANTILE SPINAL MUSCULAR ATROPHY
Biopsy as well as autopsy studies of a child who died 8 weeks after birth from the acute infantile form of spinal muscular atrophy revealed classical morphological changes, including degeneration and loss of motoneurons in the spinal cord, loss of large myelinated fibres in anterior roots and neurogenic atrophy in muscle. New ultrastructural findings include massive muscle cell elimination by apoptosis with the formation of membrane-bound muscle cell fragments, apoptotic bodies. In addition, numerous immature muscle fibres were observed. The morphological findings raise the possibility that in a severely growth-retarded muscle, the process of muscle cell apoptosis removes the peripheral tar…
A new familial congenital myopathy in children with desmin and dystrophin reacting plaques.
In 5 children with a progressive congenital myopathy representing 3 different families, unusual histological, immunohistochemical and ultrastructural changes in skeletal muscle have been found. Histologically, this myopathy was characterized by the presence of fine hyaline plaques devoid of oxidative as well as ATPase enzyme activities. At the ultrastructural level plaques were composed of helical filaments and amorphous dense material. Helical filament storage corresponded to strong desmin as well as ubiquitin immunoreactivity. In addition they were also dystrophin positive. The exclusive appearance of desmin, ubiquitin and dystrophin positive plaques in muscle specimens from 5 children em…