Among the synaptic biomarkers, SNAP25 had the highest AUC (AUC = 0.79, CI: 0.70–0.87, p < 0.001), followed by Ng (AUC = 0.69, CI: 0.59–0.79, p = 0.001) and NPTX2 (AUC = 0.63, CI: 0.52–0.73, p = 0.019) to discriminate bvFTD from AD. Here, NPTX2 is linked to Alzheimer disease.