Rapidly progressive disease (defined as a ≥50% decline in eGFR over ≤3 months and >50% crescentic glomeruli on kidney biopsy) has a poor prognosis116 and qualifies for urgent treatment with glucocorticoids and cyclophosphamide.102 Staphylococcus-associated GN with dominant IgA staining should be ruled out in these cases.117 Early treatment with glucocorticoids is also recommended for patients with IgA nephropathy and minimal change-like lesions.118. Here, CD79A is linked to IgA glomerulonephritis.