In patients with ANCA-PR3 immunocomplex glomerulonephritis and other overlapping manifestations suggesting systemic disease, it is important to recognize and aggressively treat any possible coexisting bacterial endocarditis, This is the most important step for a favorable patient outcome, including complete clinical and pathohistological resolution of the glomerulonephritis. The gene discussed is PRTN3; the disease is bacterial endocarditis.