Severe anterograde amnesia with extensive hippocampal degeneration in a case of rapidly progressive frontotemporal dementia.

Frontotemporal dementia (FTD) is usually characterized as a spectrum of relatively slowly progressive disorders with largely focal frontal or temporal presentations. The development of clinical and research criteria for discriminating FTD from Alzheimer's disease has relied, in part, on the relative preservation of episodic memory in FTD. We present a patient with FTD who, in addition to the more typical behavioural and language deficits, had a profound anterograde amnesia at the time of diagnosis. Neuroimaging confirmed atrophy of frontal and temporal lobes bilaterally, most marked in the anterior left temporal region. At post-mortem, non-Alzheimer pathology resulting in devastating cell loss was revealed in the hippocampi, as well as in the frontal and temporal cortex, thus providing neuroanatomical corroboration of the episodic memory deficit. Progression of the disease was extraordinarily rapid, with just 2 years between reported onset and time of death. This case demonstrates that the pattern of FTD may include severe anterograde amnesia as a prominent and early consequence of the disease.