Once testing is completed, the doctor will review all information (medical history, physical, neurological, mental status, and laboratory exams and brain scans) to make a diagnosis. For many forms of dementia, it is not possible for the doctor to say that someone "definitively" has a particular type of dementia. This is because making a definite diagnosis of many forms of dementia is only possible when an autopsy is performed (after death) to confirm the presence of damage or abnormal proteins in the brain.
However, the doctor will likely provide you with a diagnosis of probable or possible dementia. For example, for a person with symptoms of Alzheimer’s disease (AD), the doctor may arrive at one of two conclusions:
A person who is just starting to show small signs of dementia and does not have enough symptoms for a diagnosis of Alzheimer’s disease may be given a diagnosis of mild cognitive impairment.
After diagnosis, your physician will talk to you about a treatment plan that will best help your loved one. It is important to remember that there is not a cure for Alzheimer’s disease or for most forms of dementia. However, treatment may help slow down the progression of the disease and improve daily functioning, allowing more opportunities for good times with your loved one.
Source: Elder Care
Description: This article discusses the differential diagnosis of dementia.
Source: Alzheimer's Association
Description: This web page describes that an evaluation of individuals with symptoms of dementia is important because some causes of cognitive impairment are treatable or reversible. It also provides an overview of symptoms and diagnostic procedures.
Source: American Academy of Family Physicians
Description: This detailed medical article discusses aspects of making a diagnosis of dementia, including a guide to differential diagnosis in the form of a flow chart. The article is written for physicians.