Clinical and histopathological study of merosin-deficient and merosin-positive congenital muscular dystrophy

The clinical features of merosin-positive congenital muscular dystrophy (CM D) and merosin-deficient CMD are well known, with those of merosin-deficien t CMD being more severe. Whether the severity of histopathological findings correlates with these clinical features remains unanswered. In this study, the clinical and histopathological findings of 39 merosin-deficient and 37 merosin-positive CMD patients were compared. Merosin-deficient CMD patient s were found to be younger with earlier onset of symptoms, age of diagnosis , and a more severe clinical state (reflecting maximum motor capacity and c ontractures). On histopathological evaluation, endomysial fibrosis, perimys ial fibrosis, and histopathological state (reflecting fibrosis, adiposis, n ecrosis, and variation in fiber size) were more severe in merosin-deficient CMD. There was a con-elation between clinical and histopathological states only in merosin-deficient CMD.