Antineutrophil Cytoplasmic Autoantibody-Negative Pauci-Immune Crescentic Glomerulonephritis in a Patient with Systemic Lupus Erythematosus.

Renal involvement in systemic lupus erythematosus is usually exhibited as lupus nephritis, which is a form of immune complex-mediated glomerulonephritis and one of the most severe organ manifestations of systemic lupus erythematosus. The pathogenesis involved glomerular immune complex deposition, which leads to glomerular inflammation and typically shows a "full-house" pattern on immunofluorescence microscopy. Other forms of glomerulonephritis are rarely observed in patients with systemic lupus erythematosus. Pauci-immune crescentic glomerulonephritis is the pattern of injury most commonly observed in patients with antineutrophil cytoplasmic autoantibody-associated glomerulonephritis. The characteristic histological feature of pauci-immune crescentic glomerulonephritis is focal necrotizing and crescentic glomerulonephritis with little or no glomerular staining for immunoglobulin by immunofluorescence microscopy. We report a rare case of antineutrophil cytoplasmic autoantibody-negative pauci-immune crescentic glomerulonephritis in a patient with systemic lupus erythematosus.