Optic nerve atrophy and whole and regional brain atrophy in Leber's hereditary optic neuropathy with multiple sclerosis-like disease with m.11778G>A mutation.

Leber's hereditary optic neuropathy (LHON) is a maternally inherited form of mitochondrial optic nerve degeneration with bilateral optic atrophy. Its coexistence with multiple sclerosis (MS)-like disease (LHON-MS) is rare and also known as Harding's syndrome. The presence of LHON-MS complicates the diagnosis of optic neuritis associated with MS, which can delay the correct diagnosis and necessary treatment. Here we report optic nerve atrophy in a patient with LHON-MS coexistent with severe global and regional brain atrophy. Furthermore, we also reviewed the available literature on this rare clinical entity.