[P1-202] A fulminant and late onset case of Leigh syndrome without developmental delay due to T9176C mutation of mitochondrial ATPase 6 gene
Leigh syndrome is a severe neurodegenerative encephalopathy, usually early-onset in infancy presenting developmental delay and gray matter lesions. We reported a 12-year-old boy with an unusual late-onset Leigh syndrome with normal development, and rapidly aggravated to death within 2 months. A maternally inherited T9176C mutation of mitochondrial ATPase 6 gene was detected in the individual,which was nearly homoplasmic (>99%) in the tissues examined and was considered causal reason of the disease. The initial presentations were sudden ptosis and somnolence. Brain MRI lesions included not only the basal ganglia and brain stem, but also the bilateral white matter. However, it was rarely reported before and hard to be understood in Leigh syndrome the features combining the normal development, late onset, rapid progression with the paradoxical higher tissue homogenicity of the mutation in this case, highlighting the variability of phenotypes of Leigh syndrome.