Atypical frontotemporal lobar degeneration with ubiquitin-positive, TDP-43-negative neuronal inclusions

作者：Mackenzie Ian R A^*; Foti Dean; Woulfe John; Hurwitz Trevor A

来源：Brain, 2008, 131(5): 1282-1293.

DOI：10.1093/brain/awn061

• frontotemporal lobar degeneration
• frontotemporal dementia
• FTLD-U
• ubiquitin
• TDP-43

Frontotemporal lobar degeneration with ubiquitinated inclusions (FTLD-U) is the most common neuropathology associated with the clinical syndrome of frontotemporal dementia (FTD). Recently, TDP-43 was identified as the ubiquitinated pathological protein in both FTLD-U and sporadic amyotrophic lateral sclerosis. Although a number of studies have now confirmed that most sporadic and familial cases of FTLD-U are TDP-43 proteinopathies, there are exceptions. We describe six cases of early onset FTD with FTLD-U pathology that was negative for TDP-43, which we refer to as atypical FTLD-U. All cases were sporadic and had very early onset FTD (mean age 35 years), characterized by severe progressive psychobehavioural abnormalities in the absence of significant aphasia, cognitive-intellectual dysfunction or motor features. The neuropathological features were highly consistent, with small, round, neuronal cytoplasmic inclusions that were immunoreactive for ubiquitin (ub-ir), but negative for tau, alpha-synuclein, intermediate filaments and TDP-43. Cytoplasmic inclusions were most numerous in the neocortex, dentate granule cells and hippocampal pyramidal neurons. Ub-ir neuronal intra-nuclear inclusions were also present in neocortical and hippocampal neurons and had the unusual appearance of straight, curved or twisted filaments. We believe that these cases represent a new entity that is clinically and pathologically distinct from all currently recognized subtypes of FTLD. Moreover, the existence of such cases indicates that the designations of FTLD-U and TDP-43 proteinopathy should not be considered to be synonymous.

• 出版日期2008-5