What are the types of autoantibodies that have been associated with CNS involvement in SLE
International Society of Nephrology and the Renal Pathology Society Classification of Renal Biopsies
| Class | Clinical Manifestations | Histology Description | Light Microscopy | EM or IF |
|---|---|---|---|---|
| I/Minimal mesangial | None | Mesangial immune deposits by IF +/– EM | ||
| II/Mesangial proliferative | Microscopic hematuria +/– proteinuria; rare HTN | Mesangial hypercellularity or mesangial matrix expansion; few subepithelial/subendothelial deposits by IF or EM | ||
| III/Focal A = active lesions C = chronic lesions | Hematuria and proteinuria +/– HTN, decreased GFR, or nephrotic syndrome | <50% of glomeruli affected; IF almost uniformly involved; EM-immune deposits +/– mesangial area and in subendothelial space | Segmental proliferation wire loops Note areas of cellular hyperproliferation and areas that are spared | Note mesangial deposits |
| IV/Diffuse IV-S = segmental IV-G = global A = active lesions C = chronic lesions | Hematuria, proteinuria (frequently nephrotic), cellular casts, and generally decreased GFR; HTN is common; Hypocomplementemia and elevated dsDNA also seen frequently | >50% involvement of glomeruli; generalized hypercellularity of mesangial and endothelial cells; IF-full house pattern, extensive deposition; EM-immune complexes in both subendothelial and subepithelial distributions | Note hypercelluarlity of mesangial area and early formation of a crescent | Subendothelial deposits Note dark areas proximal to the basement membrane which visually look like thickened loops on LM |
| V/Membranous | Extensive proteinuria with minimal hematuria or renal function abnormalities | Granular global or segmental subepithelial immune deposits by IF or EM | Note thickened capillary loops without proliferation within the mesangial areas | Subepithelial deposits Note dark areas distal to the basement membrane |
| VI/Advanced sclerosing | Chronic kidney disease | >90% global glomerulosclerosis thought 2/2 lupus nephritis; no activity |
EM, electron microscopy; GFR , glomerular filtration rate; HTN, hypertension; IF, immunofluorescence.Pathology slides courtesy of Patrick D. Walker, MD, Director of Arkana Laboratories.
