Segawa Syndrome, a Dramatic Response to Dopamine.

Segawa syndrome usually manifests as dystonia, disturbance of gait with fatigue, and may be confused with spasticity. Also known as dopamine-responsive dystonia (DRD), it should be considered in any child who presents with paroxysmal or progressive hypertonia of unknown etiology, which responds dramatically to levodopa. It is a clinical diagnosis, but the level of pterins in cerebrospinal fluid and guanosine triphosphate cyclohydrolase-1 (GTCH 1) gene mutation testing done by molecular genetic testing are confirmatory.

Dopa-Responsive Dystonia: An Early Presentation of Ataxia-Telangiectasia.

Ataxia-telangiectasia (AT) is a complex genetic neurodegenerative disease with autosomal recessive inheritance. The typical initial features of ataxia telangiectasia include ataxia, cutaneous telangiectasia, and immune deficiency with recurrent infections. Usually, movement disorder occurs late in the course of the disease.

Relevance of Fluorodopa PET Scan in Dopamine Responsive Dystonia and Juvenile Parkinsonism: A Systematic Review.

Background: Dopamine Responsive Dystonia (DRD) and Juvenile Parkinsonism (JP) are two diseases commonly presenting with parkinsonian symptoms in young patients. Current clinical guidelines offer a diagnostic approach based on molecular analysis. However, developing countries have limitations in terms of accessibility to these tests.

Chromosomal-level genome of velvet bean (Mucuna pruriens) provides resources for L-DOPA synthetic research and development.

Mucuna pruriens, commonly called velvet bean, is the main natural source of levodopa (L-DOPA), which has been marketed as a psychoactive drug for the clinical management of Parkinson's disease and dopamine-responsive dystonia. Although velvet bean is a very important plant species for food and pharmaceutical manufacturing, the lack of genetic and genomic information about this species severely hinders further molecular research thereon and biotechnological development. Here, we reported the first velvet bean genome, with a size of 500.

The simple and rapid quantification method for L-3,4-dihydroxyphenylalanine (L-DOPA) from plant sprout using liquid chromatography-mass spectrometry.

L-3,4-dihydroxyphenylalanine (L-DOPA) is one of the important secondary metabolites of plants and has been used for various purposes, such as in clinical treatment for Parkinson's disease and dopamine-responsive dystonia. In plants, L-DOPA is a precursor of many alkaloids, catecholamines, and melanin; the L-DOPA synthesis pathway is similar to that in mammals. L-DOPA acts as an allelochemical, has an important role in several biological processes, such as stress response and metabolism, in plants.

Inherited metabolic diseases mimicking hereditary spastic paraplegia (HSP): a chance for treatment.

The syndromic group of hereditary spastic paraplegias has a heterogeneous clinical profile and a broad differential diagnosis, including neurometabolic disorders that are potentially treatable. This group includes 5,10-methylenetetrahydrofolate reductase deficiency, cobalamin C deficiency disease, dopamine responsive dystonia, cerebrotendinous xanthomatosis, biotinidase deficiency, GLUT1 deficiency syndrome, delta-e-pyrroline-carboxylase-synthetase deficiency, hyperonithinemia-hyperammonemia-homocitrullinuria syndrome, arginase deficiency, multiple carboxylase deficiency, and X-linked adrenoleukodystrophy. This review describes these diseases in detail, highlighting the importance of early diagnosis and effective treatment aiming at preserving functionality and quality of life in these patients.

A Case of GCH-1 Mutation Dopa-Responsive Dystonia Requiring High Doses of Levodopa for Treatment.

Background: Mutations in the GCH-1 gene are associated with Autosomal Dominant Dopamine Responsive Dystonia (DYT 5). One of the hallmarks of this condition is dramatic and sustained response to low doses of levodopa.

Case Report: We present the case of a 22 year old female patient with genetically confirmed GCH-1 Dopa-Responsive Dystonia who had no response to low dose Levodopa but who achieved symptom control on a total dose of 900 mg/day.

Anesthetic nuances in Segawa's syndrome: A case report and review of the literature.

Segawa's syndrome, dopamine-responsive dystonia, is a rare genetic disorder that typically begins in childhood by around 4-6 years of age. It is characterized by abnormal gait and dystonia. A 33-year-old man presented for autologous skin grafting of a nonhealing wound under general anesthesia.

Targeted sequencing of Parkinson's disease loci genes highlights SYT11, FGF20 and other associations.

Genome-wide association studies (GWAS) have identified numerous loci associated with Parkinson's disease. The specific genes and variants that drive the associations within the vast majority of these loci are unknown. We aimed to perform a comprehensive analysis of selected genes to determine the potential role of rare and common genetic variants within these loci.

Tremor pathophysiology: lessons from neuroimaging.

Purpose Of Review: We discuss the latest neuroimaging studies investigating the pathophysiology of Parkinson's tremor, essential tremor, dystonic tremor and Holmes tremor.

Recent Findings: Parkinson's tremor is associated with increased activity in the cerebello-thalamo-cortical circuit, with interindividual differences depending on the clinical dopamine response of the tremor. Although dopamine-resistant Parkinson's tremor arises from a larger contribution of the (dopamine-insensitive) cerebellum, dopamine-responsive tremor may be explained by thalamic dopamine depletion.

The Interaction of Genetic Mutations in PARK2 and FA2H Causes a Novel Phenotype in a Case of Childhood-Onset Movement Disorder.

Mutations in the gene have been implicated in the pathogenesis of early-onset Parkinson's disease. We present a case of movement disorder in a 4-year-old child from consanguineous parents and with a family history of Dopamine responsive dystonia, who was diagnosed with early-onset Parkinson's disease based on initial identification of a pathogenic mutation. However, the evolution of the child's clinical picture was unusually rapid, with a preponderance of pyramidal rather than extrapyramidal symptoms, leading to re-investigation of the case with further imaging and genetic sequencing.

Striatal Cholinergic Interneurons in a Knock-in Mouse Model of L-DOPA-Responsive Dystonia.

Striatal cholinergic dysfunction is a common phenotype associated with various forms of dystonia in which anti-cholinergic drugs have some therapeutic benefits. However, the underlying substrate of striatal cholinergic defects in dystonia remain poorly understood. In this study, we used a recently developed knock-in mouse model of dopamine-responsive dystonia (DRD) with strong symptomatic responses to anti-cholinergic drugs, to assess changes in the prevalence and morphology of striatal cholinergic interneurons (ChIs) in a model of generalized dystonia.

Diagnosing dopamine-responsive dystonias.

The clinical spectrum of dopamine-responsive dystonias (DRDs) has expanded over the last decade to comprise several distinct disorders. At the milder end of the clinical spectrum is the autosomal-dominant guanosine triphosphate cyclohydrolase deficiency syndrome (GTPCH-DRD), and at the more severe end is the much less common autosomal recessive tyrosine hydroxylase deficiency syndrome (TH-DRD), with intermediate forms in between. Understanding the pathophysiology of DRDs can help in their optimal diagnosis and management.

Dopamine-Responsive Growth-Hormone Deficiency and Central Hypothyroidism in Sepiapterin Reductase Deficiency.

Sepiapterin reductase (SR) deficiency is a rare autosomal recessively inherited error of tetrahydrobiopterin (BH4) biosynthesis, resulting in disturbed dopaminergic and serotonergic neurotransmission. The clinical phenotype is characterized by dopa-responsive movement disorders including muscular hypotonia, dystonia, and parkinsonism. Due to the rarity of the disease, the phenotype of SR deficiency is far from being completely understood.

Movement Disorders in Autosomal Dominant Cerebellar Ataxias: A Systematic Review.

Autosomal dominant cerebellar ataxias (ADCAs) are clinically heterogeneous disorders classified according to genetic subtype and collectively known as SCAs. In a few SCAs, movement disorders can be the most frequent extracerebellar sign. The aim of this article is to perform a systematic review of movement disorders frequency and characteristics in ADCAs.

The Anatomy of the Medial Lemniscus within the Brainstem Demonstrated at 3 Tesla with High Resolution Fat Suppressed T1-Weighted Images and Diffusion Tensor Imaging.

The medial lemniscus is part of the main somatosensory pathways ascending within the brainstem. It is formed by the heavily myelinated axons of the second order neurones of the dorsal column nuclei. This pathway ascends through the rostral medulla, pons and mesencephalon to finally terminate by synapsing with third order neurones in the ventral posterior nucleus of the thalamus.

New perspectives on dystonia.

Dystonia is a syndrome of sustained muscular contractions with numerous underlying etiologies. This review examines the varied phenomenology of dystonias, its evolving classification including recent genetic data as well as its clinical investigation and treatment. Although age of onset, anatomical distribution and family history are key elements of the investigation of dystonia, classification increasingly relies on etiologic and genetic criteria.