While there is no official diagnosis for Parkinson’s disease, it is still incredibly important to correctly diagnose a patient for therapeutic and prognostic purposes. An investigation done to show the diagnostic accuracy for the disease showed that 74% of the patients taking antiparkinsonian medication had a confirmed diagnosis of parkinsonism and 53% have Parkinson’s disease. Parkinsonism is a motor syndrome that results in rigidity, tremors, and bradykinesia. About 80% of Parkinsonism cases are caused by Parkinson’s disease. Another set of clinicopathological studies were done in the UK and Canada which showed that clinicians diagnose about 25% patients with the disease incorrectly. It is believed that the most common reason for misdiagnosis was the presence of tremors and atypical Parkinson’s disease symptoms. Some infrequent diagnostic errors included diagnosing patients with Alzheimer’s disease and dementia with Lewy bodies. As the knowledge of the heterogeneous clinical presentation of the different parkinson’s disease variations increases, the diagnostic accuracy in specialized movement-disorder units has improved. Other reasons for improved clinical diagnostic decisions include MRI’s, genetic testing, and other DNA imaging tests.

Citation: Tolosa E, Wenning G, Poewe W. The diagnosis of Parkinson’s disease. Lancet Neurol. 2006 Jan;5(1):75-86. doi: 10.1016/S1474-4422(05)70285-4. PMID: 16361025.