Parkinsonism

### Make the Diagnosis: Parkinsonism

Parkinson disease remains a clinical diagnosis. No accurate laboratory or radiologic test is currently available. An acute challenge with levodopa, followed by monitoring for improvement of symptoms, is not useful diagnostically.

#### Prior Probability

Parkinson disease affects 1% of people older than 65 years and 2% of those older than 85 years.2 The prevalence among older patients presenting with general neurologic complaints is almost certainly much higher, but precise figures are unavailable.

#### Population for Whom Parkinson Disease Should Be Considered

Adults with a tremor or other symptoms noted in Tables 38-4 and 38-5 (see Figure 38-2 for assessment of bradykinesia).

Table 38-4Useful Symptoms for Detecting Parkinson Disease
Table 38-5Useful Signs for Detecting Parkinson Disease
###### Figure 38-2

Glabella Tap Test

#### Detecting the Likelihood of Parkinson Disease

See Tables 38-4 and 38-5 (see Figure 38-2 for assessment of bradykinesia).

#### Reference Standard Tests

Serial clinical examinations performed by a specialist.

### Original Article: Does This Patient Have Parkinson Disease?

#### Clinical Scenario

A 68-year-old man presents with a 3-month history of right arm tremor at rest. His movements have been slower and he has difficulty getting out of a chair. Physical examination reveals rigidity in the upper limbs. He walks with small steps and has limited ability to swing his arms. His facial expressions are limited.

#### Why Answer This Question With a Clinical Examination?

With a prevalence estimated between 150 and 200 per 100 000, Parkinson disease (PD) is one of the most common neurologic disorders.1 It is more prevalent in older persons, affecting 1% of those older than 65 ...

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