The diagnosis and differential diagnosis of dementia

The initial approach to the patient with memory complaints should consist of a focused history, mental status examination, and functional assessment. Patients with MCI should be monitored every 6 to 12 months for conversion to dementia. Delirium, depression, amnestic disorders, and aphasias should be considered in the differential diagnosis of memory impairment. Once a diagnosis of dementia is made, patients should have a brain CT or MRI scan and laboratory tests to assist with determining the cause. It is crucial that dementia be recognized and evaluated at the earliest stage so as to begin appropriate therapy and allow the patient to have a role in management decisions. In the future, therapies for MCI may prevent conversion to dementia. The need for early recognition makes the development of diagnostic tools, such as quantitative or functional neuroimaging, and genetic or clinical biologic markers essential.