Preexisting membranous nephropathy in allograft kidney

A case of membranous nephropathy, preexisting in a donor kidney, will be re ported. A 41-year-old man underwent a cadaver renal transplantation. An all ograft biopsy specimen obtained during the operation showed spike formation on periodic acid-silver methenamine staining and deposition of IgG along t he glomerular capillary loop on immunoperoxidase staining. Immunofluorescen ce staining for IgG remained in the specimens obtained on day 11 and after 4 weeks, but markedly decreased in the specimen obtained 7 weeks after tran splantation. Electron-dense deposits also decreased in amount, but irregula r thickening of the glomerular basement membrane with spikes, electron-luce nt washout lesions, and small amounts of electron-dense deposits remained 2 0 months after the transplantation. These findings suggest that membranous nephropathy, as well as IgA nephritis and diabetic nephropathy, resolve aft er renal transplantation and that deposition of IgG markedly decreases with in a few months after transplantation, but that complete histological resto ration of the basement membrane needs at least a few years.