[Differential diagnosis of Alzheimer's disease]

The differential diagnosis of Alzheimer's disease is a problem that arises in different circumstances. At an advanced stage of the disease the symptoms are so typical that the clinical diagnosis can be made immediately. Complementary examinations (i.e. essentially computerized tomography) are performed to exclude other causes of amnesia and dementia, notably curable dementias. The diagnosis may be more difficult at the early stage of the disease in patients with only slight disorders of memory or certain types of depression. The same applies to cases with unusual presentation, focal symptoms, episodes of confusion, or delirium and hallucinations.