Chronic mild diarrhoea, stunted growth and neuromuscular abnormalities.

This report describes a 3 year-old girl with signs of ventricular hypertrophy, short stature, and persistent diarrhoea (without steatorrhoea or creatorrhoea) which was resistant to therapy. There was no clinical evidence of myopathy but a myopathic pattern was found on electromyography. Biochemical studies revealed no abnormalities. Routine histological studies of biopsied muscle showed no obvious structural abnormalities. Examination of 1 micrometer tissue sections revealed groups of atrophic fibers. Electronmicroscopy revealed widened spaces between the myofibrils with disruption of filament arrangement. The mitochondria in the motor end-plates were very distended and almost devoid of cristae.