title: A case of membranoproliferative glomerulonephritis associated with curved fibril deposition.
abstract: BACKGROUND
  It is sometimes challenging to diagnose unsusual cases of fibrillary glomerulonephritis (FGN) and immunotactoid glomerulopathy (ITG), the rare causes of nephrotic syndrome.
  
  
  METHODS
  A 75-year-old Japanese woman presented with nephrotic syndrome, microhematuria and renal insufficiency. Renal biopsy revealed membranoproliferative glomerulonephritis (MPGN) with IgM and weak C3 deposition. Congo red stain was negative. Electron microscopy demonstrated massive fibrils in the subendothelium, mesangium and subepithelium. The fibrils were partially parallel, partially curved and 17 nm in diameter. Cryoglobulin, hepatitis B virus (HBV) antigen, hepatitis C virus (HCV) antibody or antinuclear antibody were negative.
  
  
  CONCLUSIONS
  We report a case of MPGN associated with peculiar non-amyloid fibril deposition corresponding to neither FGN nor ITG.
authors.affiliation: Department of Cardiology and Nephrology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, 036-8562, Japan. iku621@yahoo.co.jp.
authors.forename: Ikuyo
authors.initials: I
authors.lastname: Narita
authors.affiliation: Department of Cardiology and Nephrology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, 036-8562, Japan. mshimada@hirosaki-u.ac.jp.
authors.forename: Michiko
authors.initials: M
authors.lastname: Shimada
authors.affiliation: Department of Cardiology and Nephrology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, 036-8562, Japan. fujitakara.1mail@gmail.com.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Fujita
authors.affiliation: Department of Cardiology and Nephrology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, 036-8562, Japan. murakami.01@live.jp.
authors.forename: Reiichi
authors.initials: R
authors.lastname: Murakami
authors.affiliation: Department of Cardiology and Nephrology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, 036-8562, Japan. msyknkmr@hirosaki-u.ac.jp.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Nakamura
authors.affiliation: Department of Cardiology and Nephrology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, 036-8562, Japan. nnakamur@r2.dion.ne.jp.|Community Medicine, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, 036-8562, Japan. nnakamur@r2.dion.ne.jp.
authors.forename: Norio
authors.initials: N
authors.lastname: Nakamura
authors.affiliation: Department of Cardiology and Nephrology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, 036-8562, Japan. h-yamabe@lapis.plala.or.jp.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Yamabe
authors.affiliation: Department of Cardiology and Nephrology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, 036-8562, Japan. okumura@hirosaki-u.ac.jp.
authors.forename: Ken
authors.initials: K
authors.lastname: Okumura
mesh_terms: D000368:Aged; D005260:Female; D015432:Glomerulonephritis, Membranoproliferative / Q000473:pathology*; D006801:Humans