Cerebral white matter disease in children may be caused by mitochondrial respiratory chain deficiency

Several mitochondrial diseases are known to occasionally involve the cerebr al white matter, namely Leigh syndrome, Kearns-Sayre syndrome, and MELAS sy ndrome, but in these cases the major finding is alteration in the basal gan glia and brainstem. Here we report on severe diffuse white matter involveme nt and respiratory chain enzyme deficiency or mitochondrial DNA rearrangeme nt in 5 unrelated families. It is interesting that white matter lesions wer e-the only abnormal neuroradiologic feature in 3 of the 5 families, and mul tiple small cyst-like white matter lesions were found in 2 of 5 probands, R espiratory chain deficiency should be considered in the diagnosis of severe white matter involvement in childhood.