Table 2.

Lexicon of the recommended nomenclature

Term	Description	References
Symptomatic (i.e., secondary) Parkinson syndrome	A Parkinson syndrome caused by an identifiable, non-genetic cause is referred to as symptomatic or secondary Parkinson syndrome	[6]
Hereditary Parkinson’s disease	Parkinson’s syndrome, which is caused by rare or rare or less frequent pathogenic genetic variants (“mutations”); with regard to the nomenclature for hereditary Parkinson’s syndromes, we propose to follow the recommendations of the International Parkinson and Movement Disorder Society Task Force (e.g., PARK-SNCA, and PARK-GBA1)	[6–8]
Idiopathic Parkinson’s syndrome (IPS)	Idiopathic Parkinson’s syndrome with unknown cause, i.e., not symptomatic, not hereditary (the term is, therefore, not strictly speaking identical to PD)	[6]
Parkinson’s disease (PD)	Lewy body disease, which leads to Parkinson’s syndrome (the term can be used be used in the presence of a clinically manifest Parkinson’s syndrome is clinically manifest, but also for conditions that future development of Parkinson’s disease syndrome, e.g., in the case of premotor or prodromal PD)	[9–11]
Preclinical Parkinson’s disease	Lewy body disease at a very early stage, which does not yet show obvious clinical symptoms	[12]
Premotor Parkinson’s disease	Lewy body disease in the early stages, which only shows non-motor symptoms, e.g., REM sleep behavior disorder	[12]
Prodromal Parkinson’s disease	Lewy body disease in the early stages, which presents with non-motor symptoms and mild-motor signs, but does not yet meet the criteria for the diagnosis of a classic Parkinson’s syndrome	[13, 14]
Parkinson’s disease with dementia (PDD)	Lewy body disease in the advanced stage, which is associated with a neurocognitive disorder, which manifests itself at the earliest 1 year after the onset of motor symptoms	[15]
Dementia with Lewy bodies (DLB)	Neurocognitive disorder caused by a Lewy body disease. Generic term for PD with dementia and Lewy body dementia	[15]
Lewy body disease (LBD)	Disease characterized by the presence of alpha-synuclein-immunoreactive Lewy bodies and Lewy neurites in certain cortical and cortical and subcortical regions of the brain. Generic term for PD, PD with dementia and dementia with Lewy body	[16, 17]
Atypical Parkinson’s syndrome (APS)	Parkinson’s syndrome, which is caused by a neurodegenerative disease other than Lewy disease (i.e., a generic term for diseases such as a generic term for diseases such as multisystem atrophy (MSA), corticobasal syndrome (CBD) and progressive supranuclear palsy (PSP))	[6, 18]