This chapter provides a brief overview of the different forms of dementia syndromes and provides a simple algorithm for initial differential diagnosis. Rapidly progressive dementias have to be excluded which require specific investigations to detect Creutzfeldt–Jakob as well as inflammatory and autoimmune diseases. A lead symptom-based approach in patients with slowly progressive cognitive and behavioural impairments without neurological symptoms is applied: progressive and primary impairments in recent memory are characteristic of typical Alzheimer’s dementia, primary behavioural changes point to the behavioural variant of frontotemporal dementia, primary impairments of language or speech are distinctive for progressive aphasias, fluctuating impairments of attention are a hallmark of Lewy body dementia, whereas primary visuospatial impairments suggest a posterior cortical atrophy. The chapter further discusses updated vascular dementia guidelines and DSM-5 revisions of defining dementia. Current diagnostic criteria for the different dementias are referenced and the role of neuroimaging is illustrated.
Lewy Body Dementia as an Underlying Etiology for Posterior Cortical Atrophy Initially Presented with Visual Agnosia and Alexia: A Case Report
