In popular beliefs, tremor is often associated with Parkinson’s disease. That is why Parkinson’s disease is often mistaken with essential tremor, which manifests itself solely by a tremor, unlike Parkinson’s disease. The person is not inconvenienced with the slowness and rigidity typical to Parkinson’s disease.
The fundamental difference between those two states resides in the type of tremor. In Parkinson’s disease, tremor manifests itself mostly at rest and fades as the person tries to perform an action. In essential tremor, it is present when executing an action, like holding a cup. Despite this theoretical difference, differentiation between essential tremor and resting tremor associated with Parkinson’s disease in practice may be complex and is sometimes a difficult task.
Parkinsonian syndromes refer to a whole set of diseases presenting symptoms typically associated with Parkinson’s disease, such as slowness, tremor, stiffness and balance disorder, but are accompanied with additional symptoms, designated as “Parkinson Plus”.
This is the list of different diseases that may be mistaken with Parkinson’s disease:
- Progressive supranuclear palsy
- Multiple system atrophy
- Striatonigral degeneration
- Sporadic olivopontocerebellar atrophy
- Shy-Drager syndrome
- Corticobasal ganglionic degeneration
- Dementia with Lewy bodies
It may be difficult for the neurologist to make a specific diagnosis in the early stages. Differences between Parkinson’s disease and a parkinsonian syndrome are very subtle. Therefore, the presence of symptoms that are not typical to Parkinson’s disease, such as loss of vision, falls in the early stage, important cognitive losses and the discovery of atypical signs at the clinical exam may lead to a parkinsonian syndrome diagnosis.
A parkinsonian syndrome diagnosis is often confirmed after a levodopa treatment because in this case, there is no or very little response to this pharmacological treatment. Parkinsonian syndromes often have a faster progress than Parkinson’s disease and unfortunately, very few therapeutic interventions are able to alleviate the symptoms of the affected person.