[The significance of cytoplasmic body in neuromuscular diseases].

To know the significance of cytoplasmic body (CB), the incidence and histochemical characteristics of the body were examined on muscle biopsied specimens from patients with various neuromuscular diseases. The CB was identified in a variety of neuromuscular diseases including metabolic disorders, muscular dystrophies, and neurogenic atrophies. The incidence varied from biopsy to biopsy comprising up to 93% of muscle fibers. The CB was numerous in type II glycogen storage (Pompe) disease, mitochondrial myopathies, especially in ragged-red fibers, inflammatory myopathies, myotonic dystrophy, and small denervating and degenerating fibers. Since the CB was present mostly in areas with increased acid phosphatase activity, it is thought to be a secondarily induced product from focal myofibrillar degeneration.