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Myoclonus, ataxia, and hung-up knee-jerk reflexes in juvenile Huntington disease

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Myoclonus, ataxia, and hung-up knee-jerk reflexes in juvenile Huntington disease

This young woman has juvenile Huntington disease manifested by ataxia and generalized action myoclonus. She has jerky tremors (properly termed "myoclonic movements") mostly in her upper extremities, worse on intention, and hung-up knee jerks. Her gait is broad-based and unsteady. She freezes and falls on attempted turning. (Contributed by Dr. Joseph Jankovic.)

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Associated Disorders

  • Abetalipoproteinemia
  • Acquired metabolic syndromes
  • Action myoclonus renal failure syndrome
  • Adult Gaucher disease
  • Alcohol-sensitive myoclonus with dystonia
  • Alzheimer disease
  • Angelman syndrome
  • Anti-N-methyl-D-aspartate receptor encephalitis
  • Antibody-associated myoclonus syndromes
  • Antiphospholipid syndrome
  • Ataxia telangiectasia
  • Ataxia with CoQ10 deficiency
  • Ataxia with vitamin E deficiency
  • Athetosis
  • Autoimmune myoclonus syndromes
  • Ballism
  • Benign adult familial myoclonic epilepsy
  • Benign developmental movement disorders
  • Benign hereditary chorea
  • Benign idiopathic dystonia of infancy
  • Benign myoclonic epilepsy in infancy
  • Benign neonatal sleep myoclonus
  • Benign paroxysmal torticollis
  • Benign sleep myoclonus of infancy
  • Biotin responsive encephalopathy,
  • Bismuth encephalopathy
  • Bobble-head doll syndrome
  • Bradykinesia
  • Celiac disease
  • Cerebral palsy
  • Ceroid lipofuscinosis
  • Cherry-red spot myoclonus syndrome
  • Chorea
  • Cortical myoclonus
  • Corticobasal degeneration
  • Creutzfeldt-Jakob disease
  • Dentatorubral-pallidoluysian atrophy
  • Dentatorubropallidoluysian atrophy
  • Dopa-responsive dystonia
  • Dravet syndrome
  • Drug-induced movement disorders
  • Drug-induced myoclonus
  • Drug-induced myoclonus
  • Early myoclonic encephalopathy
  • Ekbom syndrome
  • Epilepsia partialis continua
  • Epilepsy progressive myoclonus type 1
  • Epilepsy with myoclonic absences
  • Epilepsy with myoclonic-atonic seizures
  • Essential tremor
  • FAME
  • Familial adult myoclonic epilepsy
  • Familial myoclonic epilepsy
  • Focal dystonia
  • Friedrich ataxia
  • GM2 gangliosidoses
  • Galactosemia
  • Generalized dystonia
  • Geniospasm
  • Glutaric aciduria
  • Gluten-associated ataxia
  • Hartnup disease
  • Head-nodding
  • Hemifacial spasm
  • Hepatic encephalopathy
  • Hypoxic-ischemic encephalopathy
  • Idiopathic inflammatory syndromes
  • Infantile shuddering attacks
  • Infectious syndromes
  • JME
  • Jitteriness
  • Juvenile Huntington disease
  • Juvenile Huntington disease
  • Juvenile myoclonic epilepsy
  • Juvenile neuronal ceroid lipofuscinosis
  • Juvenile parkinsonism
  • Lafora body disease
  • Lance-Adams syndrome
  • Late onset neuronal ceroid lipofuscinosis
  • Leigh syndrome
  • Lesch-Nyhan disease
  • Lewy body disease
  • MERRF
  • Malabsorption syndromes
  • May-White syndrome
  • Methylmalonic acidemia
  • Miller-Fischer syndrome
  • Mitochondrial encephalomyopathy
  • Mitochondrial encephalopathy
  • Multiple system atrophy
  • Myoclonic absences
  • Myoclonic epilepsy in infancy
  • Myoclonic epilepsy with ragged red fibers
  • Myoclonic seizures
  • Myoclonic status epilepticus
  • Myoclonic status in nonprogressive encephalopathies
  • Myoclonic-astatic epilepsy of childhood
  • Myoclonic-atonic seizures
  • Myoclonus-dystonia
  • Neuroacanthocytosis
  • Neurodegeneration with brain iron accumulation
  • Neurodegenerative and other dementia syndromes
  • Niemann Pick C
  • Oculogyric crisis
  • Olivopontocerebellar degeneration
  • Oppenheimer dystonia
  • Opsoclonus myoclonus
  • Opsoclonus-myoclonus
  • PMA
  • Paramyoclonus multiplex of Friedreich
  • Paraneoplastic syndromes
  • Parkinson disease
  • Paroxysmal exertional dyskinesia
  • Paroxysmal kinesigenic dyskinesia
  • Paroxysmal tonic upgaze of infancy
  • Phenylketonuria
  • Physiologic myoclonus
  • Post-infectious chorea
  • Post-pump chorea
  • Postanoxic action myoclonus
  • Postencephalitic myoclonus
  • Postinfectious cerebellitis
  • Postinfectious myoclonus
  • Progressive encephalomyelitis with rigidity and myoclonus and glycine receptor antibodies
  • Progressive myoclonic ataxia
  • Progressive myoclonus epilepsies
  • Provisional tic disorder (Transient tic disorder)
  • Ramsay Hunt syndrome
  • Refsum disease
  • Renal failure myoclonus syndrome
  • Restless legs syndrome
  • Reticular reflex myoclonus
  • SCA
  • Sandifer syndrome
  • Self-stimulatory behavior
  • Severe myoclonic epilepsy in infancy
  • Sialidosis
  • Sleep starts
  • Spasmus nutans
  • Spinal muscular atrophy
  • Spinal myoclonus
  • Spinocerebellar ataxias
  • Spinocerebellar degeneration
  • Static encephalopathies secondary to diffuse brain injuries
  • Stereotypies
  • Sydenham chorea
  • Tardive dyskinesia
  • Tic disorders
  • Tourette syndrome
  • Toxin-induced myoclonus
  • Tyrosine hydroxylase deficiency
  • Unverricht-Lundborg disease
  • Uremic encephalopathy
  • Wernicke encephalopathy
  • Wilson disease
  • Withdrawal emergent syndrome