ANSWER: B Membranous glomerulonephritis (MGN) is the most commonly described glomerular disease in IgG4-related disease. MGN was present in about 7% of cases of IgG4-related tubulointerstitial nephritis from two biopsy series studies. Other specific glomerular diseases have been reported in patients with IgG4-related disease, including IgA nephropathy/Henoch Schönlein purpura nephritis, membranoproliferative glomerulonephritis (MPGN), and mesangioproliferative immune complex glomerulonephritis. References: Alexander MP, et al. Membranous glomerulonephritis is a manifestation of IgG4-related disease. Kidney Int 2013; 83:455-462. Saeki T, et al. Membranous nephropathy associated with IgG4-related systemic disease and without autoimmune pancreatitis. Clin Nephrol 2009; 71:173-178. Morimoto J, et al....