CD79A and focal segmental glomerulosclerosis: In fact, occult HCV has been detected in up to 50% of patients with idiopathic membranous nephropathy, IgA, Focal Segmental Glomerulo Sclerosis (FSGS), Antineutrophilic cytoplasmic antibody (ANCA) positive vasculitis and membranoproliferative GN [62], while occult HBV has been identified in selected cases of idiopathic membranous nephropathy and IgA, where viral antigens were found in renal tissue, in absence of viremia [63].