Membranous glomerulonephritis associated with the Guillain-Barré syndrome.

A 63-year-old white man had simultaneous onset of the Guillain-Barré syndrome and the nephrotic syndrome, three weeks after having an upper respiratory tract infection. Many granular casts were noticed in the urine sediment. Renal biopsy specimens showed early membranous glomerulonephritis and acute interstitial nephritis by light microscopy, with fine granular deposition of IgG, IgM, and C3 along the basement membrane by immunofluorescence. Electron microscopy revealed subepithelial electron-dense deposits (Stage 1 membranous glomerulonephritis). The association of these two syndromes is rare, although evidence of immunologic dysfunction has been described in both. The recent literature is reviewed and possible pathogenetic mechanisms are discussed.