Case report: Sequential complement inhibition and BAFF/APRIL blockade in progressive IgA nephropathy and IgA vasculitis nephritis: a report of two cases.

Rapidly progressive IgA nephropathy (IgAN) and IgA vasculitis nephritis (IgAVN) are characterized by marked glomerular inflammation, extensive extracapillary proliferation, and rapid renal function decline. Despite increasing insights into their shared pathogenic mechanisms, optimal treatment strategies remain uncertain. Here, we report two patients with rapidly progressive crescentic disease, one with primary IgAN and one with IgAVN, who received sequential complement inhibition combined with BAFF/APRIL blockade. Both patients showed substantial reductions in proteinuria and stabilization of kidney function during follow-up. These cases suggest that multi-pathway targeted therapy may represent a promising approach for selected patients with aggressive IgAN or IgAVN.