McArdle's disease in an elderly woman.

We have described a woman who was 71 years old when McArdle's disease was first diagnosed. She had few symptoms even during severe myoglobinuria. Muscle breakdown occurred upon relatively mild exertion. Others of her kindred had elevated serum creatine kinase levels and reported stiffness and muscle weakness upon relatively mild exertion. This case demonstrates the need to be alert to relatively mild manifestations of metabolic diseases.