On the day of diagnosis of PVAN, patients with class B disease were characterized by the highest median level of decoy cell [43/10 HPF, range (0-125/10 HPF)], urine BK viral load [6.00×109 copies/ml, range (8.10×105−1.20×1012copies/ml)], and plasma BK viral load [5.34 ×104 copies/ml, (0–5.20×106copies/ml)], compared to class A and C PVAN (Table 1). Here, KNG1 is linked to BK-virus nephropathy.