Clinical clue | Differential diagnosis | Recommended initial investigations |
---|---|---|
Acute onset dystonia or rapidly progressive course | Structural lesion External insult* Autoantibody-associated movement disorder ADEM Infection | Neuroimaging Neuroimaging Autoantibodies in serum and CSF Neuroimaging, CSF Neuroimaging, serum, CSF |
Unilateral dystonia† | Structural lesion External insult* Autoantibody-associated movement disorder Demyelinating disease‡ Antiphospholipid syndrome§ CP | Neuroimaging Neuroimaging Autoantibodies in serum and CSF Neuroimaging, CSF Serum investigations Neuroimaging |
Psychiatric symptoms (de novo) | Autoantibody-associated movement disorder Infection | Autoantibodies in serum and CSF Neuroimaging, serum, CSF |
Seizures (de novo) | Structural lesion Autoantibody-associated movement disorder Rasmussen's syndrome¶ Infection | Neuroimaging Autoantibodies in serum and CSF Neuroimaging Neuroimaging, serum, CSF |
Signs of meningo-encephalitis or encephalitis | Autoantibody-associated movement disorder Infection | Autoantibodies in serum and CSF Neuroimaging, serum, CSF |
Abnormal birth or perinatal history | CP | Neuroimaging |
Local signs of autonomic disturbances and pain | CRPS I | Clinical diagnosis** |
*External insults include head trauma and hypoxic insults caused by near-drowning, cardiac arrest or status epilepticus.
†Unilateral dystonia comprises either focal or hemidystonia.
‡Demyelinating diseases including ADEM, multiple sclerosis and neuromyelitis optica.
§Antiphospholipid syndrome with or without associated rheumatic disease such as systemic lupus erythematosus should be considered in all children with hemidystonia of unknown origin.
¶In Rasmussen's syndrome, dystonia can be an accompanying sign or the presenting feature.
**Criteria for CRPS are described by Mersky et al, see online supplemental references (supplement 4).
ADEM, acute disseminated encephalomyelitis; CP, cerebral palsy; CRPS I, complex regional pain syndrome type I.