Differential Diagnosis

Key Facts

Parkinsonism is different from Parkinson’s disease.
Parkinsonism can be induced by multiple medications.
DaTSCAN can be used to differentiate between essential tremor and parkinsonian syndromes.

Clinical Best Practices

Diagnose PD using the UK PDS Brain Bank Diagnostic Criteria.
Diagnosis may take time and may not be definitive after first visit.
Refer to a movement disorder specialist in complex cases.

Parkinson's disease must be differentiated from other conditions, especially those presenting with tremor. Remember that parkinsonism refers to any condition that causes a combination of the movement abnormalities seen in PD—such as tremors, slow movement, impaired speech, or muscle stiffness—resulting from the loss of dopamine-containing neurons. Not everyone who has parkinsonism has Parkinson's disease.

Table of Contents

Other Diagnoses

Other Diagnoses

Other diagnoses that you should consider:

Essential tremor - may have overflow to rest in severe cases, have patient lie down to assess tremor (pearl)
Progressive supranuclear palsy (PSP) - loss of vertical eye movements
Multiple system atrophy (MSA) - marked autonomic symptoms early at time of diagnosis
Corticobasal degeneration (CBD) - alien limb, spasticity, cortical sensory loss
Diffuse Lewy bodyⁱ dementia (LBD) - early dementia presenting within 2 years of motor symptoms
Alzheimer's disease
Drug-induced parkinsonism
Vascular parkinsonism

Click here for a differential diagnosis table with information on these eight conditions.

Back to TOC

UK PDS Brain Bank Diagnosis Criteria

Differential Diagnosis Table

PD Symptoms Table

Non-motor Symptoms Questionnaire

Treatment of essential tremor: Report of the Quality Standards Subcommittee of the American Academy of Neurology

AAN Guidelines - Practice Parameter: Diagnosis and prognosis of new onset Parkinson disease

PD: The Basics

Making the Most of Your Medical Appointment

What You and Your family Should Know