[Bucillamine-associated membranous nephropathy in a patient with rheumatoid arthritis].

A case of bucillamine-associated membranous nephropathy in a patient with rheumatoid arthritis was reported. A 34 year-old woman was admitted to our hospital because of proteinuria in September, 1988. Rheumatoid arthritis had been diagnosed in April, 1988, and had been treated with bucillamine (disease modifying anti rheumatic drug) and amfenac (nonsteroidal antiinflammatory drug). The renal biopsy specimens showed Stage I membranous nephropathy, on both electron and immunofluorescence microscopy. Proteinuria decreased after the drugs were withdrawn despite continued RA symptoms. These results were consistent with drug induced nephropathy. Since bucillamine has some resemblances in its structure and pharmacologic action to D-penicillamine, which sometimes induces membranous nephropathy, it is thought that the nephropathy in this case was caused by an adverse reaction to bucillamine.