Quantitative histopathology in congenital myopathies.

A histo-morphometric analysis has been carried out in 23 muscle biopsies obtained from patients with congenital myopathies (6 nemaline m., 10 centronuclear m., 4 central core m., 3 multicore m.) in order to improve diagnosis and to confirm the data available in literature. No relationship has been found between the severity of the disease and the histo-pathological features as previously described. Nevertheless, the following pathological aspects diverge from previous reports: a) the absence of rods within the nuclei and of mitochondrial abnormalities in nemaline myopathy; b) the presence of type I fiber hypertrophy and of mitochondrial alterations in 30% of the patients with centronuclear myopathy; c) the presence of cores even in type II fibers, mitochondrial abnormalities, nucleosis, inflammatory cellular reaction and fibrosis in addition to the absence of rods in central core myopathy; d) the type I fiber hypertrophy in all patients with multicore myopathy.