The pathogenesis and treatment of IgA nephropathy.

IgA nephropathy (IgAN) is one of the most common causes of glomerulonephritis in the world. The proliferative and crescentic forms of IgA are found in up to 30% of cases and are associated with nephritic-range proteinuria, accelerated hypertension, and accelerated decline toward ESRD. Thus, it is important to investigate the mechanism of the onset of IgAN and to identify the most appropriate treatment. We herein review the pathogenesis and treatment of IgA nephropathy. As to the pathogenesis, we found that CB4 provoked exacerbation of renal pathologic findings in HIGA mice via endothelial injury, IFN-gamma production, and dysfunction of the mesangial pathway and could possibly become one of the factors involved in the mechanism of the onset or evolution of human IgAN. As to the treatment of IgAN, we evaluated the efficacy of tonsillectomy plus prednisolone, warfarin, and dipyridamole including methylprednisolone pulse therapy (tonsillectomy plus pulse therapy) and prednisolone, warfarin, and dipyridamole including mizoribine (PWDM) for the treatment of diffuse IgAN in children. These therapies were effective in ameliorating the proteinuria and histological severity of patients with IgAN. Furthermore the detail investigations into the pathogenesis of IgAN and double-blind randomized control studies on children with IgAN will be necessary.