A 32-year-old woman with SLE has nephrotic-range proteinuria with minimal hematuria and near-normal complement levels. Renal biopsy shows thickened capillary loops resembling membranous nephropathy. Immunofluorescence demonstrates granular IgG, IgA, IgM, C3, and C1q along the capillary walls. The International Society of Nephrology/Renal Pathology Society class of lupus nephritis is:
- A Class V (membranous lupus nephritis) ✓
- B Class III (focal lupus nephritis)
- C Class IV (diffuse lupus nephritis)
- D Class II (mesangial proliferative)
Explanation
Class V lupus nephritis shows subepithelial immune deposits producing a membranous pattern with global thickening of capillary walls, and it typically presents as pure nephrotic syndrome with relatively preserved renal function. The 'full house' immunofluorescence pattern (all three immunoglobulins plus both complement components) is characteristic of lupus and distinguishes it from primary membranous nephropathy, which usually shows only IgG4 and C3. Classes II, III, and IV are defined by mesangial, focal endocapillary, and diffuse endocapillary proliferation respectively.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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