Abstract

We report the clinical features and the muscle pathology in 2 patients with congenital muscular dystrophy (CMD) secondary to merosin deficiency and in 2 patients with sarcoglycan (adhalin) deficiency. Electron microscopic examination revealed sarcolemmal defects in non-necrotic muscle fibers in all cases. These pathological findings are indistinguishable from those of Duchenne/Becker muscular dystrophy. We suggest that the similarities in histological findings reflect a common pathogenetic mechanism, i.e., a structural weakening of the sarcolemma with an increased susceptibility to rupture under mechanical stress. We propose the term sarcolemmopathy as an all-encompassing rubric for these disorders. (C) 1997 by Elsevier Science Inc.