α‐Synuclein Seed Amplification in <scp>CSF</scp> and Brain from Patients with Different Brain Distributions of Pathological α‐Synuclein in the Context of Co‐Pathology and <scp>Non‐LBD</scp> Diagnoses

CSF αSyn-SAA reliably identifies αSyn seeds in patients with diffuse αSyn pathology in the context of co-pathology and non-Lewy body disease (LBD) diagnoses. The analysis of brain homogenates suggests that pathological αSyn in the amygdala might differ from pathological αSyn in the frontal cortex. The αSyn-SAA might facilitate the differential diagnosis of dementias with mixed pathologies. ANN NEUROL 2022;92:650-662.