CD79A and lipoprotein glomerulopathy: Barsoum et al.32, testing the hypothesis that serum levels and deposits of immunoglobulin A (IgA) have a significant role in kidney histology, especially in patients with accompanying liver disease, found IgA deposits in 70% of patients with class III, IV, or V glomerulopathy, compared with 29% in those with class I or II.