MPO-ANCA-Positive crescentic glomerulonephritis: a distinct entity of scleroderma renal disease?

Scleroderma renal crisis is characterized by intimal thickening of the afferent glomerular arterioles resulting in hypertension and fibrinoid necrosis of the capillary tuff. We report a 67-year-old man with long-standing systemic sclerosis who developed normotensive progressive renal failure, proteinuria, and a nephritic urinary sediment with serum myeloperoxidase-antineutrophil cytoplasmatic antibodies (MPO-ANCA). Renal biopsy showed pauci-immune crescentic glomerulonephritis but none of the typical vascular changes of scleroderma renal crisis. Because comparable cases have recently been reported from Japan, normotensive MPO-ANCA-positive crescentic glomerulonephritis may form an entity of progressive renal failure in scleroderma.