[Differential diagnosis of early dementia]

The principles of differential diagnosis are discussed of dementia in Alzheimer's disease against similar syndromes of other origin. Among the syndromes which should be differentiated from Alzheimer's disease those are considered: syndromes erroneously diagnosed as dementia, potentially reversible dementia, vascular dementia and dementia in certain degenerative diseases. In the differential diagnosis history data, results of neurological and neuropsychological examinations are helpful, while among laboratory investigations brain imaging by CT, MRI and SPECT are most important.