IgA nephropathy is a group of multiple causes of chronic glomerular disease with the same immunopathological features. Clinical about 40% ~ 45% of the patients showed gross or microscopic hematuria, 35% ~ 40% of patients showed microscopic hematuria with proteinuria, the rest showed nephrotic syndrome and renal failure. ... IgA nephropathy is a group of multiple causes of chronic glomerular disease with the same immunopathological features. Clinical about 40% ~ 45% of the patients showed gross or microscopic hematuria, 35% ~ 40% of patients showed microscopic hematuria with proteinuria, the rest showed nephrotic syndrome and renal failure. IgA nephropathy is a common worldwide glomerular disease, and the prevalence of IgA nephropathy varies widely in different continents, in different countries or in different regions of a country, such as Asia, Japan, Singapore, IgA nephropathy 50% of primary glomerular disease, while the western United States only 2% of the Indian low incidence