sTREM-1 had moderate performance (area under the curve [AUC] 0.745, 95 % CI 0.636, 0.853) to distinguish MPA and GPA patients with the upper half of BVAS, with a higher AUC compared to ESR (AUC 0.724, 95 % CI 0.608, 0.840) but lower than CRP (0.783, 95 % CI, 0.680, 0.886). Here, CRP is linked to granulomatosis with polyangiitis.