Mitochondrial abnormalities in cortical dendrites from patients with early forms of subacute sclerosing panencephalitis (SSPE).

Biopsy fragments from the frontal cortex of two patients with early forms of subacute sclerosing panencephalitis (SSPE) were studied with ultrastructural methods. Special attention was given to mitochondrial abnormalities observed in dendrites from the three superficial cortical layers. Some of the mitochondria presented atypical elongated cristae parallel to the longer axis of the organelle and closely opposite each other. The surface of these cristae is undulated, and the intracristal space is regularly septate. As these abnormal mitochondria appeared in dendrites, which in later stages of the disease are supposed to degenerate, it is advanced that these abnormalities could be precursors of dendritic changes and be possibly related to the precocious, insidious mental changes which characterize the early forms of the disease, as it is known that the disruption of the dendritic domain is linked with neuronal dysfunction.