Rapidly progressive glomerulonephritis with D-penicillamine

We present 3 cases of anti-myeloperoxidase, anti-neutrophil cytoplasmic ant ibody (MPO-ANCA)-positive rapidly progressive glomerulonephritis developed during the treatment with D-penicillamine (D-PC) for rheumatoid arthritis. Rheumatoid arthritis was diagnosed in these patients, and D-PC was administ ered to them at doses of 100, 200, and 300 mg per day for 321 42, and 39 mo nths, respectively. They developed proteinuria, hematuria, renal insufficie ncy, and anemia, and D-PC was stopped. On admission, MPO-ANCA was strongly positive in their sera. Renal biopsy showed glomerulonephritis with cellula r crescents. Immunofluorescence examination revealed deposits of granular I gG, IgM, IgA, C1q, and C3 in the mesangium. The 3 patients were treated wit h steroid pulse therapy along With administration of anticoagulants, and cy clophosphamide was also used in 2 patients. Their renal function improved g radually and MPO-ANCA disappeared after immunosuppressive treatment.