Supplementary Table 1 Examples of Clinical Thinking in Myoclonus

Supplementary Table 1 | Examples of clinical thinking in myoclonus

Associated features /

Consideration

/ Diagnostic tests
Opsoclonus / ·  Paraneoplastic syndrome
·  Postinfectious / ·  Tumor screening (lung, breast, melanoma, medulloblastoma)
·  Viral serology ± anti-neuroleukin antibodies
Epilepsy
·  During puberty
·  Young-onset epilepsy / ·  Juvenile myoclonic epilepsy
·  Progressive myoclonic encephalopathies (epilepsy and cognitive decline, myoclonus); for example, mitochondrial disease, Lafora disease, ceroid lipofuscinosis, DRPLA / ·  Mutation analysis (research setting)
·  EEG, gene mutation analysis, muscle–skin biopsy, lactate
Ataxia / ·  Spinocerebellar ataxias
·  Multiple system atrophy
·  Progressive myoclonic ataxia (for example, Unverricht–Lundborg, mitochondrial, DRPLA)
·  Metabolic disease (for example celiac disease; Wilson disease) / ·  Genetic testing
·  Gene mutation analysis, muscle biopsy, lactate
·  Celiac antibodies, duodenal biopsy; serum copper and caeruloplasmin, slit lamp examination, liver biopsy in some cases
Rapid cognitive decline / ·  Creutzfeldt–Jakob disease / ·  Cerebrospinal fluid analysis, EEG, genetic testing, tonsillar biopsy
Dystonia / ·  Familial myoclonus dystonia (DYT11) / ·  Gene mutation, family history
Nerve or root lesion / ·  Peripheral myoclonus / ·  Electrophysiological studies to establish peripheral lesion

Abbreviation: DRPLA, dentatorubropallidoluysian atrophy.