High levels of urinary soluble CD163 (a specific macrophage activation marker) were significantly associated with active renal vasculitis (9, 10).EGF (epidermal growth factor), a specific tubular marker, when measured in urine, could assess the degree of tubular damage and predict chronic kidney disease progression in patients with AAV (11–13). The gene discussed is EGF; the disease is anti-neutrophil cytoplasmic antibody-associated vasculitis.