Renal involvement is one of the extra-articular manifestations found in patients with rheumatoid arthritis (RA). Membranous glomerulonephopathy, membranoproliferative glomeruonophritis, secondary amyloidosis, and focal segmental glomerulosclerosis are reported as pathologic diagnoses of renal involvement. However, reports of renal involvement in patients with RA and antineutrophil cytoplasmic autoantibody (ANCA)-associated pauci-immune glomerulonephritis are rare. Recently, we experienced two patients with RA who developed azotemia and were finally diagnosed with ANCA-associated pauci-immune glomerulonephritis. Because of the rarity of these cases, we report two cases in patients with RA with a literature review.

Keywords: Rheumatoid arthritis, Antineutrophilic cytoplasmic antibody, Glomerulonephritis