Features of the clinical course of neurodegenerative brain disease caused by mutations in the neurophacitis and succinate dehydrogenase gene: clinical case

Abstract

Neurodegenerative diseases of the brain pose a serious challenge in diagnosis and treatment. Of particular interest are diseases caused by complex mutations, the clinical picture of which is ambiguous. The article presents a description of a clinical case of a neurodegenerative disease of the brain with symmetrical damage to the cerebellar hemispheres in the projection of the dentate nuclei, in the region of the superior and middle cerebellar peduncles, in the region of the midbrain tegmentum, along the corticospinal tracts, in the subcortical sections of the frontoparietal regions of the brain. It has been shown that these clinical manifestations are caused by the formation of small foci of demyelination in the white matter of the brain. The cause of the disease was revealed to be a deficiency of mitochondrial complex II, nuclear type 4, which is caused by mutations in the NFASC (encoding neurofascin) and SDHB (encoding succinate dehydrogenase) genes. The leading clinical manifestations in this case were motor disorders in the form of persistent bilateral ptosis, external ophthalmoplegia, optic disc atrophy, retinal pigmentary degeneration, subcortical dysarthria, sensorineural hearing loss, and cognitive impairment. However, the clinical picture of this disease developed latently for a long time, which made its diagnosis difficult. The reason for this was a complex genetic defect including mutations in the neurofasciitis and succinate dehydrogenase gene. The paper provides a discussion of currently known effective methods of treating the disease.