O1‐02‐02: Prediction of neuropathology in primary progressive language and speech disorders

Frontotemporal lobar degeneration (FTLD) encompasses heterogeneous clinicopathological entities. The ante mortem prediction of the underlying pathological lesions is reputed to be difficult or even impossible, whatever the clinical variant. This study aimed to characterize the correlations between the different clinical variants of primary progressive language and speech disorders and the pathological diagnosis. Pathological diagnosis was available for 17 patients prospectively followed-up in the Lille (France) Memory Clinic between 1993 and 2008. These cases were diagnosed with progressive anarthria (n = 5), agrammatic progressive aphasia (n = 6), logopenic progressive aphasia (n = 1), progressive jargon aphasia (n = 2), typical semantic dementia (n = 1) and atypical semantic dementia (n = 2). All cases of progressive anarthria had a tauopathie at post mortem evaluation: PSP (n = 2), Pick disease (n = 2) and corticobasal degeneration (n = 1). All cases of agrammatic primary progressive aphasia had ubiquitine and TDP-43 positive FTLD (FTLD-U). The case of logopenic progressive aphasia and the cases of progressive jargon aphasia had Alzheimer's disease (AD). The typical case of semantic dementia had FTLD-U. The cases of atypical semantic dementia had tauopathies: argyrophilic grains disease (AGD) and corticobasal degeneration. The different anatomical distribution of the pathological lesions could explain these good correlations: opercular and subcortical regions in tauopathies with progressive anarthria, left frontotemporal cortex in FTLD-U with agrammatic progressive aphasia, bilateral lateral and anterior temporal cortex in FTLD-U or AGD with semantic dementia, left parietotemporal cortex in AD with logopenic progressive aphasia or jargon aphasia.