Topic Discussion: IgM Nephropathy

1. Initial was seen in 1978, 12 cases reported.
2. Pathology findings: mesangial proliferation, diffuse granular C3 and IgM, EM with foot process effacement and mesangial deposits ( exclusion criteria includes FSGS and Lupus Nephritis or systemic vasculitis)
3. Appears like minimal change with mesangial deposits - so steroid resistance is clinical picture as well
4. More common in children than adults
5. There is debate in the literature if this entity is real vs a part of spectrum of minimal change disease or immune complex GN with mesangial deposits.
6. Post transplant recurrent cases have been reported.
7. IgM deposition without accompanying deposits or renal dysfunction or proteinuria has been noted in many cases of donors.
8. Some studies have shown circulating IgM heavy molecules( aggregates and immune complexes ) in the serum in IgM nephropathy.

http://www.ncbi.nlm.nih.gov/pubmed/12552495
http://ndt.oxfordjournals.org/content/19/10/2650.full
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1541770/