Menkes kinky hair disease with 'ragged red' fibers.

A 30-month-old infant with Menkes kinky-hair disease died, with prominent vascular, cerebral and cerebellar degeneration. Increased numbers of mitochondria containing homogeneous dense bodies were seen on electron-microscopic examination of Purkinje cells. Subsarcolemmal aggregates of mitochondria ('ragged red' fibers) were present in skeletal muscle. These mitochondrial alterations support the hypothesis that copper deficiency results in mitochondrial encephalomyopathy.