New insight into the pathogenesis of the ‘idiopathic nephrotic syndrome’

Abstract

The incidence of idiopathic nephrotic syndrome (INS) is estimated to be 20-30 cases per million children and three cases per million adults per year. Different histological patterns are associated with the disease such asminimal-change glomerulonephritis (MCGN) and focal segmental glomerulosclerosis (FSGS), which can both be associated with various degrees of mesangial cell proliferation. Whether these two pathological forms of INS are two extremes of a single disease with different evolutions or represent two unique diseases remains a point of discussion. MCGN is a more benign glomerulonephritis which is largely sensitive to glucocorticoids and/or to other immunosuppressive drugs (cyclophosphamide, cyclosporin A), while FSGS is poorly responsive to these drugs and usually progresses to end-stage renal failure. Nevertheless, the prognosis associated with FSGS can be influenced by more aggressive and/or prolonged treatments [1]. In addition, the histologically apparent recurrence of FSGS after kidney transplantation demonstrates that early MCGN can result in FSGS within a few weeks or months [2].