Prognostic factors of IgA nephropathy presenting with mild proteinuria at the time of diagnosis (a multicenter cohort study).

Background: Clinical factors affecting renal prognosis in patients with immunoglobulin A nephropathy (IgAN) and low urinary protein excretion (U-Prot) remain unclear. This study evaluated such factors in patients with clinical grade I (CG-I) IgAN with U-Prot < 0.5 g/day.