Argyrophilic grain disease presenting as behavioral frontotemporal dementia.

Argyrophilic grain disease (AgD) is a frequent late-onset 4R tauopathy of old age characterized by the presence of profuse spindle-shaped argyrophilic grains (AGs). It is a neurodegenerative disorder that is clinically characterized by a slow progressive amnestic mild cognitive impairment similar to Alzheimer's disease. In rare instances, it is characterized as a behavioral-variant frontotemporal dementia (bv-FTD). In this study, we report a case with typical clinical and neruoimaging features of bv-FTD, who had autopsy findings consistent with a definitive diagnosis of AgD. We suggest that AgD might be included in the differential diagnosis of patients presenting with bv-FTD.