The 13513G>A mutation in the ND5 gene of
mitochondrial DNA (
mtDNA) is usually associated with
mitochondrial encephalomyopathy with
lactate acidosis and
stroke-like episodes (
MELAS), or
Leigh syndrome (LS). In this study, we describe three young Chinese patients with
MELAS/LS overlap syndrome who carried the m.13513G>A mutation. Clinical and MRI features were characteristic of both
MELAS and LS. Interestingly, the clinical presentation of this overlap syndrome could be variable depending on the degree of relative contribution of
MELAS and LS, that is,
MELAS as the initial presenting syndrome, LS as the predominant syndrome, or both
MELAS and LS appearing at the same time. The final brain MRI showed findings characteristic of both
MELAS and LS, with asymmetrical lesions in the cortex and subcortical white matter of the occipital, temporal, and frontal lobes (
MELAS), and bilateral and symmetrical lesions in the basal ganglia and brainstem (LS). Brain autopsy in one case revealed
infarct-like lesions in the cerebral cortex, basal ganglia and brainstem, providing further insight into the distribution of the pathological lesions in
MELAS/LS overlap syndrome. This is the first report of the brain pathological changes in a patient with m.13513G>A mutation. The spatial distribution of
infarct-like lesions in the brain could explain the symptoms in
MELAS/LS overlap syndrome.