In the current study, the group in which prednisolone was used also had a significant decrease in urinary protein and a significant increase in serum C3 levels at the last follow-up, suggesting that even patients with C3GN with nephrotic syndrome or severe proteinuria (urinary protein creatinine ratio ≥ 1.0 g/gCr) may have favorable outcomes with prednisolone. Here, C3 is linked to nephrotic syndrome.