Non-IgA mesangioproliferative glomerulonephritis

Waikhom et al studied clinicopathological features and outcome of 57 patients diagnosed with non-IgA mesangioproliferative glomerulonephritis (non-IgA GN). The majority of them presented with nephrotic syndrome and responded to steroid treatment. However, some patients progressed to late stage chronic kidney disease. The authors concluded that non-IgA GN may not be a benign entity as previously suggested in some studies.

non-IgAN was diagnosed when the kidney biopsies showed mesangial hypercellularity but without IgA staining by immunofluorescence. A majority (60%) showed staining with other Igs and complement with IgG being the most common. Electron microscopy (EM) was not performed. Crescents, focal synechiae were identified in some patients. The crescents, C3 deposit and lack of treatment response correlated with poor renal function at 36 months.

Comment: Non-IgAN in the study most likely represent a heterogeneous group of glomerular diseases. There were both biopsies with negative and positive immune deposits. The positive group also had a diverse staining with IgG, IgM, C3 and C1q. There were no indication whether the stainings were present in mesangium or glomerular capillary walls. The IF negative group could be minimal change disease, focal and segmental glomerulosclerosis in which mesangial cell proliferation can sometime be found. The positive immune deposits group could be resolving postinfectious glomerulonephritis or mesangial lupus nephritis. With the absence of description whether there was capillary wall staining and EM study, there is a possibility that membranous nephropathy was also included into this group.