AUTHOR=Wagemann Olivia , Brendel Matthias , Franzmeier Nicolai , Nübling Georg , Gnörich Johannes , Zaganjori Mirlind , Prix Catharina , Stockbauer Anna , Wlasich Elisabeth , Loosli Sandra V. , Sandkühler Katja , Frontzkowski Lukas , Höglinger Günter , Levin Johannes TITLE=Feasibility and potential diagnostic value of [18F]PI-2620 PET in patients with down syndrome and Alzheimer’s disease: a case series JOURNAL=Frontiers in Neuroscience VOLUME=Volume 18 - 2024 YEAR=2025 URL=https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2024.1505999 DOI=10.3389/fnins.2024.1505999 ISSN=1662-453X ABSTRACT=Purpose of the reportAdults with Down Syndrome (DS) have a substantially increased risk for Alzheimer’s disease (AD) due to the triplicated amyloid-precursor-protein gene on chromosome 21, resulting in amyloid and tau accumulation. However, tau PET assessments are not sufficiently implemented in DS-AD research or clinical work-up, and second-generation tau tracers such as [18F]PI-2620 have not been thoroughly characterized in adults with DS. We aim at illustrating feasibility and potential diagnostic value of tau PET imaging with [18F]PI-2620 for the diagnosis of DS-AD.Materials and methodsFive adults with DS (40% female, aged 43–62) and cognitive decline underwent clinical assessments, neuropsychological testing, lumbar puncture and multimodal neuroimaging. All underwent [18F]PI-2620 tau PET. Visual read of tau PET scans was performed by three blinded raters, assessing increased tracer uptake in brain areas corresponding to the six Braak stage regions and basal ganglia.ResultsVisual read of tau burden revealed three tau-positive individuals which corresponded to their clinical decline while two cognitively stable individuals were rated as negative. Rating showed high inter-rater reliability for all Braak stages.ConclusionTau PET imaging is a feasible and important biomarker assessment in the differential diagnosis of cognitive decline in adults with DS at risk of developing AD.