Immunoglobulin A nephropathy (IgAN) is the most common type of glomerulonephritis worldwide and an important cause of end-stage renal disease. IgAN has a variable clinical presentation: it is of minimal clinical significance in many people and rarely may cause rapidly progressive kidney failure in others. However, typical in nephrology practice is a slowly progressive course, characterized initially by hematuria and persistent proteinuria before arterial hypertension, followed by a progressive decrease in glomerular filtration rate (GFR), supervenes.