FORTNIGHTLY REVIEW - PARKINSONISM - RECOGNITION AND DIFFERENTIAL-DIAGNOSIS

The cumulative lifetime risk of a person developing parkinsonism has been estimated at 1 in 40 Idiopathic Parkinson's disease is the commonest cause, but about a third of patients with the syndrome of parkinsonism or a diagnosis of Parkinson's disease have some other disease instead The diagnosis of Parkinson's disease is entirely clinical, but the results of certain investigations may help in recognising alternative causes for parkinsonism For a diagnosis of established parkinsonism, upper body akinesia must be present; rigidity is usually, but not always, present; tremor is an optional extra The two conditions that are most commonly misdiagnosed as Parkinson's disease—essential tremor and arteriosclerotic pseudoparkinsonism—do not display true parkinsonism. © 1995, BMJ Publishing Group Ltd. All rights reserved.