Dataset Information

Neuroimaging in mitochondrial disorders.

ABSTRACT: Mutations in either nuclear DNA or mitochondrial DNA can result in disruption of oxidative phosphorylation and lead to mitochondrial dysfunction. Mitochondrial disease manifestations occur predominantly in the central nervous system, peripheral nervous system, and/or involve several organ systems. The consequences range from manifestations of a single organ or tissues, such as muscle fatigue, if confined only to muscle, seizures, intellectual disabilities, dementia, and stroke (if to the central nervous system), leading to disability or even early death. The definitive diagnosis of a mitochondrial disorder can be difficult to establish. Criteria and checklists have been established and are more reflective of adult disease. However, in children, when symptoms suggest a mitochondrial disease, neuroimaging features may have more diagnostic impact and additionally these can be used to follow the course, evolution, and recovery of the disease. This review will demonstrate the common neuroimaging patterns in patients with mitochondrial disorders and point out how various newer neuroimaging modalities may be exploited to glean information as to the different aspects of mitochondrial dysfunction or resulting neurological and cognitive disruption, although reports in the literature using these methods remain sparse.

SUBMITTER: Gropman AL

PROVIDER: S-EPMC3625392 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Neuroimaging in mitochondrial disorders.

Gropman Andrea L AL

Neurotherapeutics : the journal of the American Society for Experimental NeuroTherapeutics 20130401 2

Mutations in either nuclear DNA or mitochondrial DNA can result in disruption of oxidative phosphorylation and lead to mitochondrial dysfunction. Mitochondrial disease manifestations occur predominantly in the central nervous system, peripheral nervous system, and/or involve several organ systems. The consequences range from manifestations of a single organ or tissues, such as muscle fatigue, if confined only to muscle, seizures, intellectual disabilities, dementia, and stroke (if to the central ...[more]

PMID: 23208728

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Project description:Primary mitochondrial disorders are a group of clinically variable and heterogeneous inborn errors of metabolism (IEMs), resulting from defects in cellular energy, and can affect every organ system of the body. Clinical presentations vary and may include symptoms of fatigue, skeletal muscle weakness, exercise intolerance, short stature, failure to thrive, blindness, ptosis and ophthalmoplegia, nystagmus, hearing loss, hypoglycemia, diabetes mellitus, learning difficulties, intellectual disability, seizures, stroke-like episodes, spasticity, dystonia, hypotonia, pain, neuropsychiatric symptoms, gastrointestinal reflux, dysmotility, gastrointestinal pseudo-obstruction, cardiomyopathy, cardiac conduction defects, and other endocrine, renal, cardiac, and liver problems. Most phenotypic manifestations are multi-systemic, with presentations varying at different age of onset and may show great variability within members of the same family; making these truly complex IEMs. Most primary mitochondrial diseases are autosomal recessive (AR); but maternally-inherited [from mitochondrial (mt) DNA], autosomal dominant and X-linked inheritance are also known. Mitochondria are unique energy-generating cellular organelles, geared for survival and contain their own unique genetic coding material, a circular piece of mtDNA about 16,000 base pairs in size. Additional nuclear (n)DNA encoded genes maintain mitochondrial biogenesis by supervising mtDNA replication, repair and synthesis, which is modified during increased energy demands or physiological stress. Despite our growing knowledge of the hundreds of genetic etiologies for this group of disorders, diagnosis can also remain elusive due to unique aspects of mitochondrial genetics. Though cure and FDA-approved therapies currently elude these IEMs, and current suggested therapies which include nutritional supplements and vitamins are of questionable efficacy; multi-center, international clinical trials are in progress for primary mitochondrial disorders.

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Dataset Information

Neuroimaging in mitochondrial disorders.

Publications

Neuroimaging in mitochondrial disorders.

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