In this prospective study, we aimed to investigate the association of serum (s) and urine (u) levels of IP-10, galectin-9, and SIGLEC-1 with disease activity in patients with active SLE (renal and extrarenal) compared to patients with inactive SLE (renal and extrarenal), patients suffering from active renal disease of ANCA-associated vasculitis (AAV) and healthy volunteers. Here, LGALS9 is linked to anti-neutrophil cytoplasmic antibody-associated vasculitis.