PPIB and early-onset autosomal dominant Alzheimer disease: We refer to the four multiple system atrophy cases with discrepancy between amyloid-β and tau pathology as ‘amyloid-β-predominant Alzheimer’s disease neuropathologic change-multiple system atrophy’ to distinguish these from multiple system atrophy with primary age-related tauopathy or multiple system atrophy with typical Alzheimer’s disease neuropathologic change.