GLOMERULONEPHRITIS-MEMBRANOPROLIFERATIVE GN

SUMMARY

1. MPGN (a biopsy diagnosis) is associated with primarily lupus, and HCV-associated cryoglobulinemia.

2. Pathology is marked by activation of complement, and about 50% of the time the complement levels are low.

3. MPGN is one of the diseases that can present either as nephritic/nephrotic or combined nephritic-nephrotic.

4. Immune complex-mediated MPGN: results from the deposition of immune complexes in the glomeruli as a result of chronic infection (hepatitis C and B). Low C3 and low C4 common.

5. Complement-mediated MPGN: due to mutation in proteins that regulate the alternate pathway resulting in overactivity.

6. The low C3 in PIGN returns to normal after 2-3 months; but in patients with MPGN, it stays low indefinitely. If you suspected PIGN & C3 stays low > 3 mths, suspect MPGN instead, get a renal biopsy!

7. Treatment is aimed at the underlying cause, includes plasmapheresis for cryoglobulinemia.



DDD: Dense Deposit Disease

Reference(s)

Wilkinson, I., Furmedge, D. and Sinharay, R. (2017). Oxford handbook of clinical medicine. Oxford: Oxford University Press. Get it on Amazon.
Feather, A., Randall, D. and Waterhouse, M. (2020). Kumar And Clark’s Clinical Medicine. 10th ed. S.L.: Elsevier Health Sciences. Get it on Amazon.
Hannaman, R. A., Bullock, L., Hatchell, C. A., & Yoffe, M. (2016). Internal medicine review core curriculum, 2017-2018. CO Springs, CO: MedStudy.
Therapeutic Guidelines. Melbourne: Therapeutic Guidelines Limited. https://www.tg.org.au [Accessed 2021].