Brief practical clinical diagnostic criteria for the neurodegenerative diseases in the elderly

In the literature there is need of clinical and instrumental characterization of all neurodegenerative diseases. Particular attention deserves the timing of the onset of motor or cognitive symptoms, which is extremely useful issue giving the frequent overlapping between neurodegenerative diseases. Aim of this review is to provide a description of typical clinical and imaging features of all neurodegenerative diseases, especially idiopathic Parkinson’s disease (PD) and Alzheimer’s disease (AD). Particular attention will be devoted to the cluster of symptoms at the moment of the diagnosis. Based on early starting symptoms (cognitive or extrapiramidal) we will introduce criteria to differentiate AD from fronto-Temporal Dementia (FTD), Lewy bodies dementia (DLB) and Vascular dementia (VaD), and between PD, Vascular Parkinsonism (VP) and DLB. All these diseases are characterized by cognitive deficits. PD will be suspected if cognitive impairment occurs at least one year after the onset of the motor symptoms while VP and DLB are more likely if cognitive deficits and motor symptoms appear simultaneously. Finally, we will focus on parkinsonian signs plus other motor symptoms at the time of the diagnosis. The presence of cerebellar or pyramidal signs, with falls and autonomic dysfunction, with or without cognitive deficit should help to consider potential causes of atypical parkinsonism including cortical-basal degeneration (CBD), multiple system atrophy (MSA) and progressive supranuclear palsy (PSP).