Abstract: TH-PO126

The Characteristics of Membranoproliferative Glomerulonephritis (MPGN) at a Single Center in Japan

Session Information

Category: Glomerular

  • 1004 Clinical/Diagnostic Renal Pathology and Lab Medicine

Authors

  • Nakano, Marie, Tokyo Women's Medical University Hospital, Tokyo, Japan
  • Karasawa, Kazunori, Tokyo Women's Medical University Hospital, Tokyo, Japan
  • Kumon, Saeko, Tokyo Women's Medical University Hospital, Tokyo, Japan
  • Kamiyama, Takahiro, Tokyo Women's Medical University Hospital, Tokyo, Japan
  • Moriyama, Takahito, Tokyo Women's Medical University Hospital, Tokyo, Japan
  • Nitta, Kosaku, Tokyo Women's Medical University Hospital, Tokyo, Japan
Background

MPGN has been recently proposed new classification, and alternative pathway (AP) mediated MPGN (C3 glomerulopathy), which was defined as isolated C3 deposition and absent of immunoglobulin deposition, has been recognized as a different glomerulonephritis from Immune complex (IC) mediated MPGN. However, there was no report analyzed about the difference of these two nephritis in Japan.

Methods

We reclassified 87 MPGN patients diagnosed between 1977 and 2014 in our institution according to the new classification. The clinical, pathological features and outcomes of patients between IC mediated MPGN and AP mediated MPGN were analyzed.

Results

Among 55 MPGN patients except 32 secondary MPGN, there were 42 IC mediated MPGN patients and 13 AP mediated. In the baseline clinical findings, the estimated glomerular filtration rate were similar between both groups (89.69 vs. 76.19, p=0.2581). The amount of proteinuria (2.34 vs. 5.20 d/day, p=0.0063), C3 (39.0 vs. 67.25, p=0.0317), and CH50 (22.4 vs. 36.4, p=0.0404) were significantly lower, and serum albumin was significantly higher (3.40 vs. 2.70, p=0.0186) in AP mediated MPGN than IC mediated MPGN. In the pathological findings, there were no significance in light microscopical findings, but all immunofluorescence staining except C3 were significantly higher in IC mediated MPGN. Immunosuppression therapy was used in 92.3% patients in AP mediated MPGN, and 90.5% in IC mediated. The 400 months renal survival rate were similar between both groups (70.0 vs. 74.0%, P=0.445).

Conclusion

We have shown that AP mediated MPGN had similar prognosis in comparison to IC mediated MPGN, though proteinuria at baseline was lower than IC mediated MPGN. Lower serum complements were resulted from higher alternative pathway activation, and this phenomenon might induce the poor prognosis in AP mediated MPGN, though their lower proteinuria.