A form of congenital muscular dystrophy.

Five children, between 2 and 10 years old, 3 boys and 2 girls, two of them siblings, showed mild clinical and morphological congenital muscular dystrophy. Neuromuscular signs and symptoms being present from birth or early infancy, aggravated only insignificantly during the course of the disease. Three patients developed right ventricular hypertrophy after the age of 9 years, of whom 2 died of cardiac failure at the age of 11 years. There was probably no cardiomyopathy; pulmonary hypertension of unclear range or slightly elevated. The EMG showed abnormal but non-specific features. A myopathic fiber diameter spectrum, intrafascicular fat cells and mild endomysial fibrosis as well as insufficient fiber typing and type I predominance were prominent in histopathological findings. Ultrastructurally, abnormal myofibers were present in each biopsy although the fine structural pathology was non-specific. The families of the patients came from a genetic isolate in the North-Eastern region of the Federal Republic of Germany. The first 4 patients were genetically related to each other by several links among their families dated back over the last 3 centuries. The fifth patient came from the same area, but unequivocal familial linkage could not be established. An autosomal recessive mode of inheritance is suggested for this congenital muscular dystrophy.