28. International Society of Nephrology 2003 classification of lupus nephritis Chronic lesions and sclerosis Advanced sclerosing Class VI Predominantly nephrotic disease Membranous Class V >50% of glomeruli involved Diffuse proliferative Class IV <50% of glomeruli involved Focal proliferative Class III Hypercellular on light microscopy Mesangial proliferative Class II Normal light microscopy findings, abnormal electron microscopy findings Minimal mesangial Class I