β-Amyloid (A β) deposition in the medial temporal lobe of patients with dementia with Lewy bodies

Abstract

The distribution and density of diffuse, primitive and classic β-amyloid (A β) deposits in the medial temporal lobe (MTL) was studied in cases of dementia with Lewy bodies (DLB) with and without associated Alzheimer's disease (AD) and 15 cases of sporadic AD. In the `pure' DLB cases, virtually no A β deposits were observed in the CA regions of the hippocampus or dentate gyrus whereas deposits were distributed throughout the MTL in DLB/AD and AD cases. Densities of diffuse and primitive A β deposits were similar in AD and DLB/AD cases but density was significantly reduced in the `pure' DLB cases. The density of the classic deposits was significantly reduced in DLB cases with or without associated AD compared with AD cases. These results suggest that A β deposition in the (MTL) in `pure' DLB cases is similar to that of elderly non-demented patients while, with the exception of the classic deposits, A β deposition in DLB/AD cases is similar to that in cases of AD alone.