Variable Details
Lewy body disease
Pathologic diagnosis of Lewy body disease - 4 stages
This variable replaces dlbdx.
Pathologic diagnosis of Lewy body disease describes 4 stages of distribution of a-synuclein in the brain based on algorithm and neuropathologist's opinion. Sections (6 µm) of paraffin-embedded brain tissue (from midfrontal, middle temporal, inferior parietal, anterior cingulate, entorhinal cortices, amygdala, and substantia nigra) were stained for α-synuclein immunostain (Zymed laboratories, LB509; 1:100) with alkaline phosphatase as the color developer. Since 2011, immunohistochemistry has been performed with phosphorylated α-synuclein (Ser129) Monoclonal Antibody (Wako Chemicals USA, pSyn#64, 1:20,000).
McKeith criteria (McKeith et al., 1996) were modified to assess the following categories of Lewy body disease:
| Value | Coding |
|---|---|
| 0 | Not present |
| 1 | Nigral predominant |
| 2 | Limbic-type |
| 3 | Neocortical type |
Nigral Lewy bodies were identified as round, intracytoplasmic structures with a darker halo. In the cortex, Lewy bodies were identified as round intracytoplasmic structures, often lacking any halo and with an eccentric nucleus. Only intracytoplasmic Lewy bodies were used as an indicator of positive staining.
Note: Both limbic type and neocortical Lewy body disease - are considered "cortical" Lewy body disease; however in our study (and others) only neocortical are related to dementia.