Diagnostic Criteria for Parkinson's Disease: From James Parkinson to the Concept of Prodromal Disease.

The diagnosis of Parkinson’s disease (PD) is based on clinical features and differently to the common opinion that detecting this condition is easy, seminal clinico-pathological studies have shown that up one-fourth of patients diagnosed as PD during life has an alternative diagnosis at post-mortem. The misdiagnosis is even higher when only the initial diagnosis is considered, since the diagnostic accuracy improves by time, during follow-up visits. Given that the confirmation of the diagnosis of PD can be only obtained through neuropathology, to improve and facilitate the diagnostic-therapeutic workup in PD, a number of criteria and guidelines have been introduced in the last three decades.…