Yoshida et al. demonstrated that MPA patients with high affinity MPO-ANCA mainly presented with rapidly progressive glomerulonephritis and histological findings consistent with focal/crescentic glomerulonephritis, whereas MPA patients with low affinity MPO-ANCA mainly displayed clinical signs of chronic renal failure and mixed/sclerotic glomerulonephritis [53]. This evidence concerns the gene MPO and chronic kidney disease.