(3) The threshold concentration of AnxA1 for distinguishing SCAP from non-SCAP was 254.13 ng/mL, with 84.6% sensitivity and 64.0% specificity; and the ROC curve analysis indicated that combining AnxA1 with CURB-65 score increased the prediction of SCAP. Here, ANXA1 is linked to syringocystadenoma papilliferum.