Membranoproliferative glomerulonephritis, p-antineutrophil cytoplasmic antibodies, and rheumatoid arthritis. Report of a case.

Many rheumatoid arthritis patients have renal dysfunction induced either by the drugs used to treat their joint disease or by the chronic inflammation. A case of rheumatoid arthritis with p-antineutrophil cytoplasmic antibodies and mesangial glomerulonephritis that progressed to type I membranoproliferative glomerulonephritis is reported. The glomerular abnormalities were diagnosed by two renal biopsies done at a one-year interval. Reasons for the first and second renal biopsies were renal dysfunction with hematuria and impure nephrotic syndrome, respectively. Unusual features in this case include the succession of two histologic forms of glomerular disease in a patient with rheumatoid arthritis, the correlation between p-antineutrophil cytoplasmic antibody titers and activity of the renal disease. In addition, type I membranoproliferative glomerulonephritis is exceedingly rare in rheumatoid arthritis patients.