Alzheimer's disease.

All patients with dementia should be investi- gated fully * The commonest cause of dementia is Alzheimer's disease * Alzheimer's disease can be diagnosed with certainty only on histology * Deposition of 3 amyloid protein is a central feature * Some rare familial cases are associated with mutations in the amyloid precursor protein gene * Associated neurotransmitter deficits, such as for acetylcholine, are amenable to treatment Box 1-Clinical syndrome ofdementia * Acquired deficit of cognition * Multiple domains of cognitive impairment * Must include memory impairment * Cognitive impairment not due to disturbance of arousal * Can be reversible For criteria of of dementia see