Table 4. Abbreviated International Society of Nephrology/Renal Pathology Society (ISN/RPS) classification of lupus nephritis (2003)

a Indicate the proportion of glomeruli with active and with sclerotic lesions.
b Indicate the proportion of glomeruli with fibrinoid necrosis and cellular crescents.
c Class V may occur in combination with class III or IV in which case both will be diagnosed.
Indicate and grade (mild, moderate, severe) tubular atrophy, interstitial inflammation and fibrosis, severity of arteriosclerosis or other vascular lesions.
Class IMinimal mesangial lupus nephritis
Class IIMesangial proliferative lupus nephritis
Class IIIFocal lupus nephritisa
Class IVDiffuse segmental (IV-S) or global (IV-G) lupus nephritisb
Class VMembranous lupus nephritisc
Class VIAdvanced sclerosing lupus nephritis