Simultaneous occurrence of perimembranous glomerulonephritis and glomerular amyloidosis.

The results of electron microscopic examination of renal biopsies from 3 patients with rheumatoid arthritis treated with penicillamine are presented. All 3 patients developed a nephrotic syndrome upon discontinuation of penicillamine therapy. When viewed with the electron microscope, segmental forms of perimembranous glomerulonephritis (Stages I-II of Ehrenreich and Churg) and glomerular renal amyloidosis Grade I-III were observed. In all three cases the nephrotic syndrome was considered to be due to the simultaneous occurrence of the two disease processes. In 2 cases perimembranous glomerulonephritis with immuno-complex-deposits was assumed to be the dominant factor in the causation of the disease, in the other case amyloidosis was the principle abnormality.