Frontal Variant of Alzheimer's Disease: A Report of a Novel PSEN1 Mutation.

Alzheimer's disease may mimic frontotemporal dementia. We describe a case of presenile dementia who presented with peudo-psychotic symptoms carrying a PSEN1 mutation (P355 S), which was not known to be pathogenic. PET-FDG showed bilateral frontotemporal hypometabolism, but at MRI, multiple microbleeds were detected, suggestive of amyloid angiopathy.