Which pathology is commonly associated with certain frontotemporal dementia subtypes, including ubiquitin-positive inclusions and tau pathology seen in corticobasal degeneration and progressive supranuclear palsy?

• A. Alzheimer's disease pathology
• B. Frontotemporal dementia
• C. Lewy body pathology
• D. Vascular pathology

Answer: (B)

Frontotemporal dementia pathology explains the neuropathologic substrates seen across its subtypes. FTLD encompasses different protein inclusions: many cases show ubiquitin-positive inclusions due to TDP-43 proteinopathy, while others are FTLD-tau with tau inclusions seen in corticobasal degeneration and progressive supranuclear palsy. This diversity within a single clinical syndrome—frontotemporal dementia—accounts for the ubiquitin-positive and tau pathologies described. By contrast, Alzheimer's disease pathology centers on amyloid plaques and tau tangles, Lewy body pathology on alpha-synuclein, and vascular pathology on vascular lesions; these are not the primary substrates linked to the frontotemporal dementia subtypes discussed.