1 Minute Read: Parkinson’s Disease Differential Diagnosis

The Isabel 1 Minute Read program highlights various diseases and conditions, providing the Isabel tool differential list. Subscribe to the Isabel blog to receive clinical content and articles.

Parkinson's disease (synonyms: Parkinson disease, Parkinson's, Idiopathic Parkinson disease, paralysis agitans) is a one of the most common neurodegenerative disorders.   Prevalence increases with age and the main features are resting tremor, rigidity, bradykinesia and postural instability.  These symptoms are termed parkinsonism or a “parkinsonian syndrome.”  The mean onset of Parkinson's disease is age 65 years, but cases can occur at a younger age.  If a case occurs in a person under 21 years of age, then it is classified as juvenile parkinsonism, and in ages 21 to 40 years, it is called young-onset parkinsonism.

A patient's diagnosis is normally made based on medical history and a neurological examination.  Sometimes a dopaminergic agent is trialed, and if there is relief in motor impairment, then this is normally used as confirmation of Parkinson’s disease.  Other brain scans may be performed to rule out other diagnoses which could also present with similar symptoms to Parkinson’s disease.

This differential diagnosis of Parkinson’s disease includes:

Lewy body dementia presents with dementia, hallucinations, fluctuating mental status. 

Progressive supranuclear palsy presents with gaze palsies and early falls within 1 year of diagnosis.

Segawa’s Syndrome is characterized by subtle signs of Parkinsonism which may include slowness of movement (bradykinesia), stiffness and resistance to movement (rigidity), balance difficulties, and postural instability.

Autonomic failure like Multiple system atrophy where there is a poor response to levodopa, autonomic dysfunction or speech/bulbar/pyramidal or cerebellar dysfunction.

Drug-induced movement disorders can present like Parkinson’s disease if the client is on medication like  antipsychotics of  chlorpromazine or flupentixol, anti-emetics like Prochlorperazine or Metoclopramide,  antidepressants – selective serotonin reuptake inhibitors or lithium used to treat bipolar disorder.

Wilson’s disease with onset of Parkinsonism prior to age 40 should be tested for this by measuring ceruloplasmin level and ophthalmologic examination for Kayser-Fleischer rings.

Kayser-Fleischer ring, diagnostic of Wilson's disease which can present with signs of Parkinsonism and differentiate between Parkinson's Disease

Other differentials to consider for Parkinson's disease include cerebral infarction, carbon monoxide toxicity and Fahr's disease.