Juvenile Pearson syndrome.

The clinical and magnetic resonance imaging findings of a 14-year-old boy with Pearson syndrome are presented. The patient represents the oldest living survivor of the original four patients described by Pearson and associates. This syndrome has recently been found to be associated with an mtDNA deletion. The patient reported here has a deletion similar but not identical to that reported in the literature. Several mitochondrial myopathies have been associated with mtDNA deletions, with considerable overlap between and among the phenotypes and underlying mtDNA deletions. The same may well prove to be true for Pearson syndrome.