Genetic heterogeneity and respiratory chain enzyme analysis in pediatric Indian patients with mitochondrial disorder: Report of novel variants in POLG1 gene and their functional implication using molecular dynamic simulation.

Mitochondrial disorders are a heterogeneous group of disorders caused by mutations in the mitochondrial DNA or in nuclear genes encoding the mitochondrial proteins and subunits. Polymerase Gamma (POLG) is a nuclear gene and mutation in the POLG gene are one of the major causes of inherited mitochondrial disorders. In this study, 15 pediatric patients, with a wide spectrum of clinical phenotypes were screened using blood samples (n = 15) and muscle samples (n = 4).

Pediatric Movement Disorders and Neuromodulation: An Overview.

Pediatric movement disorders are heterogeneous and complex disorders with various aetiologies. These are broadly classified as hypo and hyperkinetic disorders. Genetic causes of basal ganglia dysfunction or direct injuries to the basal ganglia mark the genesis of these abnormal movements.

Leukodystrophies and Genetic Leukoencephalopathies in Children Specified by Exome Sequencing in an Expanded Gene Panel.

The overlapping clinical and neuroimaging phenotypes of leukodystrophies pose a diagnostic challenge to both clinicians and researchers alike. Studies on the application of exome sequencing in the diagnosis of leukodystrophies are emerging. We used targeted gene panel sequencing of 6440 genes to investigate the genetic etiology in a cohort of 50 children with neuroimaging diagnosis of leukodystrophy/genetic leukoencephalopathy of unknown etiology.

Mitochondrial leukoencephalopathies: A border zone between acquired and inherited white matter disorders in children?

Background: There is emerging evidence implicating mitochondrial dysfunction in the pathogenesis of acquired demyelinating disorders such as multiple sclerosis. On the other hand, some of the primary mitochondrial disorders such as mitochondrial leukoencephalopathies exhibit evidence of neuroinflammation on MRI. The inter-relationship between mitochondrial disorders and episodic CNS inflammation needs exploration because of the therapeutic implications.

Outcome of epilepsy in patients with mitochondrial disorders: Phenotype genotype and magnetic resonance imaging correlations.

Objectives: Studies exploring the outcome of epilepsy in patients with mitochondrial disorders are limited. This study examined the outcome of epilepsy in patients with mitochondrial disorders and its relation with the clinical phenotype, genotype and magnetic resonance imaging findings.

Patients And Methods: The cohort was derived from the database of 67 patients with definite genetic diagnosis of mitochondrial disorders evaluated over a period of 11years (2006-2016).

Mitochondrial oxidative phosphorylation disorders in children: Phenotypic, genotypic and biochemical correlations in 85 patients from South India.

Mitochondrial oxidative phosphorylation (OXPHOS) disorders account for a variety of neuromuscular disorders in children. In this study mitochondrial respiratory chain enzymes were assayed in muscle tissue in a large cohort of children with varied neuromuscular presentations from June 2011 to December 2013. The biochemical enzyme deficiencies were correlated with the phenotypes, magnetic resonance imaging, histopathology and genetic findings to reach a final diagnosis.

Audiological manifestations in mitochondrial encephalomyopathy lactic acidosis and stroke like episodes (MELAS) syndrome.

Objectives: Reports of audiological manifestations in specific subgroups of mitochondrial disorders are limited. This study aims to describe the audiological findings in patients with MELAS syndrome and m.3243A>G mutation.

Peripheral neuropathy in genetically characterized patients with mitochondrial disorders: A study from south India.

Background: There are relatively few studies, which focus on peripheral neuropathy in large cohorts of genetically characterized patients with mitochondrial disorders. This study sought to analyze the pattern of peripheral neuropathy in a cohort of patients with mitochondrial disorders.

Methods: The study subjects were derived from a cohort of 52 patients with a genetic diagnosis of mitochondrial disorders seen over a period of 8 years (2006-2013).

Magnetic resonance imaging correlates of genetically characterized patients with mitochondrial disorders: A study from south India.

Background: Large studies analyzing magnetic resonance imaging correlates in different genotypes of mitochondrial disorders are far and few. This study sought to analyze the pattern of magnetic resonance imaging findings in a cohort of genetically characterized patients with mitochondrial disorders.

Methods: The study cohort included 33 patients (age range 18 months-50 years, M:F - 0.

Clinical and Neuroimaging Features in Two Children with Mutations in the Mitochondrial ND5 Gene.

Mutations in the mitochondrial-encoded nicotinamide adenine dinucleotide dehydrogenase 5 gene (MT-ND5) has been implicated as an important genetic cause of childhood mitochondrial encephalomyopathies. This study reports the clinical and magnetic resonance imaging findings in two pediatric patients with mutations in the ND5 gene of mitochondrial DNA. The 8-month-old boy with m.

Speech-Language and swallowing manifestations and rehabilitation in an 11-year-old girl with MELAS syndrome.

Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a rare mitochondrial disease. The available studies on MELAS syndrome are limited to evaluation of radiological, audiological, genetic, and neurological findings. Among the various neurological manifestations, speech-language and swallowing manifestations are less discussed in the literature.

Cardiac manifestations of primary mitochondrial disorders.

Objectives: One of the most frequently affected organs in mitochondrial disorders (MIDs), defined as hereditary diseases due to affection of the mitochondrial energy metabolism, is the heart. Cardiac involvement (CI) in MIDs has therapeutic and prognostic implications. This review aims at summarizing and discussing the various cardiac manifestations in MIDs.

Mitochondrial myopathy, cardiomyopathy, and pontine signal changes in an adult patient with isolated complex II deficiency.

Mitochondrial disorders resulting from an isolated deficiency of complex II of the respiratory chain is rarely reported. The phenotypic spectrum associated with these disorders is heterogeneous and still expanding. This report describes a patient who presented with myopathy, dilated cardiomyopathy, and pontine signal changes on magnetic resonance imaging.

Clinical and magnetic resonance imaging findings in patients with Leigh syndrome and SURF1 mutations.

Background: Mutation in the SURF1 is one of the most common nuclear mutations associated with Leigh syndrome and cytochrome c oxidase deficiency. This study aims to describe the phenotypic and imaging features in four patients with Leigh syndrome and novel SURF1 mutation.

Methods: The study included four patients with Leigh syndrome and SURF1 mutations identified from a cohort of 25 children with Leigh syndrome seen over a period of six years (2006-2012).

The "double panda" sign in Leigh disease.

Although the "face of the giant panda" sign on magnetic resonance imaging (MRI) is traditionally considered to be characteristic of Wilson disease, it has also been reported in other metabolic disorders. This study describes the characteristic "giant panda" sign on MRI in a child with Leigh disease. The diagnosis was based on the history of neurological regression; examination findings of oculomotor abnormalities, hypotonia, and dystonia; raised serum lactate levels; and characteristic brain stem and basal ganglia signal changes on MRI.

Electro-clinical features and magnetic resonance imaging correlates in Menkes disease.

Background: Epilepsy is an early and important feature in Menkes disease (MD), an X-linked recessive neurodegenerative disorder of childhood with defect in copper metabolism. There are only few reports on the electro-clinical and magnetic resonance imaging correlates in Menkes disease. The current study describes the electro-clinical features in MD in relation with the structural findings on MRI.