Box 2:Clinical and diagnostic features of some childhood tremors

Tremor syndrome	Clinical features	Diagnostic approach
Physiologic tremor	Postural tremor: no neurologic defects	Chemistry profile Thyroid function test Review of current medications
Essential tremor	Postural tremor: affects both hands and arms and sometimes the head; increases in amplitude with stress, fatigue and stimulants, and decreases with alcohol	No specific tests Rule out other causes
Juvenile Parkinson disease	Resting tremor: increases in amplitude with stress and disappears with voluntary movement of limb	No specific testing needed for typical presentation MRI for atypical presentations Rule out other causes
Cerebellar tremor	Intention tremor: affects both arms and legs and sometimes the head; results of finger-to-nose and heel-to-shin testing are abnormal; gait abnormalities; dysarthria; nystagmus	CT or MRI Examination of cerebrospinal fluid for IgG gamma globulins (if multiple sclerosis is suspected) Levels of toxins and alcohol (if intoxication suspected)
Wilson disease	Wing-beating tremor: associated with signs of hepatic disease (e.g., ascites or jaundice)	Liver function test Serum ceruloplasmin level Measurement of copper levels in urine Slit-lamp examination