Mitochondrial abnormalities in choroid plexus of Leigh disease.

Morphological study of the choroid plexuses in three patients with Leigh disease revealed a marked increase in the number of mitochondria in almost all of the choroidal epithelial cells. This finding is considered the morphological expression of a biochemical defect in the mitochondrial metabolism underlying Leigh disease, and the probable explanation for increased CSF levels of lactate and pyruvate in this disease.