IgA nephropathy was introduced by Berger and Hinglais in 1968 and refers to IgA-based immunoglobulin deposits in the glomerular thylakoid region and capillary collaterals on immunofluorescence examination of kidney biopsy tissue, and excludes secondary IgAN caused by allergic purpura, SLE, chronic liver disease, etc. It is the most common primary glomerular disease, accounting for 30-35% of primary glomerular disease in Asia, with a predominance in adolescents. In 2007, the Nephrology Group of the Pediatrics Branch of the Chinese Medical Association investigated 1349 cases with a 2:1 male to female ratio and a median age of onset of 9 years; in 2013, the National Working Group for the Study of the Status of Diagnosis and Treatment of Common Kidney Diseases in Children investigated 1417 cases with a 2:1 male to female ratio and a median age of onset of 10 years.