New Insights into the Pathogenesis and Treatment of Patients with Immunoglobulin A Nephropathy

Immunoglobulin A (IgA) nephropathy (also called Berger’s disease) is the most common primary chronic glomerulonephritis worldwide, and was first described by J. Berger et al in 1968. Histopathologically, IgA nephropathy is characterized by expansion of glomerular mesangial matrix with mesangial cell proliferation and/or mononuclear cell infiltration. Glomeruli typically contain generalized-diffuse granular mesangial deposits of IgA (mainly IgA1), IgG and C3. Electron-dense deposits are observed in the glomerular mesangial areas and partially in the glomerular basement membrane. Thus, this disease is considered to be an immune-complex-mediated glomerulonephritis. Clinically, patients with IgA nephropathy show microscopic and macroscopic hematuria and/or proteinuria. Advanced patients (almost 40% of patients) progress to end-stage kidney disease during 20 years of observation. However, the pathogenesis and radical treatment of IgA nephropathy have still not been established.