Class I | Minimal mesangial lupus nephritis Normal on light microscopy. Mesangial immune deposits on immunofluorescence |
Class II | Mesangial proliferative lupus nephritis Mesangial hypercellularity or matrix expansion, with mesangial immune deposits on immunofluorescence |
Class III | Focal lupus nephritis Glomerulonephritis involving < 50% of glomeruli, typically with sub-endothelial immune deposits. |
Class IV | Diffuse lupus nephritis Glomerulonephritis involving > 50% of glomeruli, typically with sub-endothelial immune deposits. Can be segmental or global. |
Class V | Membranous lupus nephritis Global or segmental sub-epithelial immune deposits |
Class VI | Advanced sclerotic lupus nephritis > 90% of glomeruli globally sclerosed without residual activity |