MPGN revisited

This week in the March 2012 issue of NEJM, Sethi and Fervenza discuss a must read article on MPGN. All the recent advances in MPGN and so called C3 glomerulopathy have been reviewed in this article.

Key points
1. EM based approach should be abandoned.  IF based approach seems more logical.
2. Immune complex mediated vs complement mediated MPGN and then looking for secondary causes.
3. Immune complex mediated usually has circulating Immunoglobulin and immune complexes and the big 3 categories are infections, autoimmune disease and MGUS. IF will show C3 and some immunoglobulin.
4. The complement based MPGN usually have capillary wall staining for C3 deposits, then  look at the EM --> if sausage shaped deposits think dense deposit disease and if not then C3 glomerular disease. Both of these are a result of dysregulation of the alternative pathway of complement.
5. Recurrence after transplantation is fair amount, The highest being if this MPGN was associated with MGUS.

Take a look at this nice summary on MPGN
Ref:
http://www.ncbi.nlm.nih.gov/pubmed/22435371