Diagnosis of secondary dystonia
What features suggest the diagnosis of secondary dystonia?
Secondary forms of dystonia, which account for 25% of cases, are suspected in patients with a history of head trauma, peripheral trauma, encephalitis, toxin exposure, drug exposure, perinatal anoxia, kernicterus, and seizures.
Abnormal findings such as dementia, ocular motility abnormalities, ataxia, spasticity, weakness, or amyotrophy are often present in patients with secondary dystonia.
Furthermore, onset of dystonia at rest instead of with action, early onset of speech involvement, hemidystonia, abnormal laboratory tests, and abnormal brain imaging suggest the diagnosis of secondary dystonia.
The list of causes of secondary dystonia is long, but it is important to try to identify those that are potentially treatable, especially Wilson’s disease and tardive dystonia
Causes of Secondary Dystonia
|Aminoacid disorders||Arteriovenous malformation|
|Glutaric aciduria||Atlantoaxial dislocation or subluxation|
|Hartnup’s disease||Brain tumor|
|Homocystinuria||Cerebellar ectopia and syringomyelia|
|Methylmalonic acidemia||Central pontine myelinolysis|
|Tyrosinosis||Cerebral vascular or ischemic injury|
|Miscellaneous metabolic disorders||Fenfluramine|
|Lesch–Nyhan syndrome||Head trauma|
|Triosephosphate isomerase deficiency||Acute infectious torticollis|
|Vitamin E deficiency||AIDS|
|Neurodegenerative disorders||Creutzfeldt–Jakob disease|
|Ataxia telangiectasia||Encephalitis lethargica|
|Azorean heredoataxia||Reye’s syndrome|
|Machado–Joseph disease||Subacute sclerosing panencephalitis|
|Familial basal ganglia calcifications||Syphilis|
|Huntington’s disease||Paraneoplastic brain stem encephalitis|
|Infantile bilateral striatal necrosis||Perinatal cerebral injury and kernicterus|
|Intraneuronal inclusion disease||Peripheral trauma|
|Progressive pallidal degeneration||Carbon monoxide|
|Progressive supranuclear palsy||Carbon disulfide|
|Wilson’s disease||Wasp sting|
NIBA , Neurodegeneration with brain iron accumulation.