MPO-ANCA associated crescentic glomerulonephritis with numerous immune complexes: case report

BMC Nephrol. 2012 Jun 1:13:32. doi: 10.1186/1471-2369-13-32.

Abstract

Background: Antineutrophil cytoplasmic antibody (ANCA)-associated crescentic glomerulonephritis (CGN) is a major cause of rapidly progressive glomerulonephritis (RPGN). ANCA-associated CGN is generally classified into pauci-immune RPGN, in which there are few or no immune complexes.

Case presentation: A 78-year-old man presented with RPGN after a 7-year course of chronic proteinuria and hematuria with stable renal function. A blood examination showed a high titer of myeloperoxidase (MPO)-ANCA. A renal biopsy showed crescentic glomerulonephritis with abundant subepithelial, intramenbranous and subendothelial deposits by electron microscopy, leading to the diagnosis of ANCA-associated CGN superimposed on type 3 membranoproliferative glomerulonephritis (MPGN).

Conclusions: This case is unique in that type 3 MPGN and MPO-ANCA-associated CGN coexisted, and no similar case has been reported to date. Because ANCA-associated CGN has a predilection for elderly individuals and primary type 3 MPGN is rarely seen in this age group, coincidental existence appears less likely. This case may confer valuable information regarding the link between immune complex and ANCA-associated CGN.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Antibodies, Antineutrophil Cytoplasmic / immunology*
  • Diagnosis, Differential
  • Glomerulonephritis / diagnosis*
  • Glomerulonephritis / immunology*
  • Humans
  • Immune Complex Diseases / diagnosis*
  • Immune Complex Diseases / immunology*
  • Male
  • Peroxidase / immunology*

Substances

  • Antibodies, Antineutrophil Cytoplasmic
  • Peroxidase