Myopathy in hyperornithinemic gyrate atrophy of choroid and retina.

Five patients in two families with hyperornithinemia and gyrate atrophy (HOGA) of the choroid and retina are reported. All patients had marked muscle wasting. Biochemical studies revealed high levels of plasma ornithine and low levels of plasma lysine. Muscle biopsies were performed in four patients and showed subsarcolemmal accumulation of pleomorphic mitochondria and tubular aggregates. These findings suggest that muscle wasting in HOGA is associated with a myopathy that is probably secondary to hyperornithinemia and/or hypolysinemia.