Membranous nephropathy vs Membranoproliferative GN
How to tell Membranous nephropathy and Membranoproliferative GN apart when a board question makes them look alike.
Membranous is subepithelial spike-and-dome nephrotic disease; MPGN is subendothelial/mesangial tram-track mixed disease.
Side by side
Adult nephrotic syndrome with diffuse capillary wall thickening and spike-and-dome deposits.
Mixed nephritic-nephrotic picture with subendothelial/mesangial deposits and tram-track basement membrane splitting.
Subepithelial immune deposits thicken the glomerular basement membrane.
Mesangial and endocapillary proliferation remodel the capillary wall.
Subepithelial immune deposits with spike-and-dome pattern on Jones silver stain, granular IgG and C3 on immunofluorescence, NORMAL serum complement, anti-PLA2R antibodies in primary disease (positive in about 70 percent), and secondary triggers (hepatitis B, SLE, syphilis, solid-tumor adenocarcinoma, NSAIDs, gold, penicillamine) support membranous nephropathy.
Subendothelial and mesangial immune deposits with tram-track double contour basement membrane on silver stain, LOW serum complement (both C3 and C4 in type I, C3 alone in type II / dense deposit disease), and secondary triggers (hepatitis C with cryoglobulinemia in type I, C3 nephritic factor in type II) support membranoproliferative glomerulonephritis.
The trap
Both names contain membrane and both are immune-complex glomerulonephritides, which is what trips students up. The biopsy phrase fixes the answer. Spike-and-dome appearance on Jones silver stain with subepithelial deposits equals membranous nephropathy (pure nephrotic syndrome with very high proteinuria and high venous thromboembolism risk, especially renal vein thrombosis). Tram-track double contour basement membrane with subendothelial and mesangial deposits equals membranoproliferative GN (mixed nephrotic-nephritic presentation with LOW complement). The complement level is the fastest split: membranous has normal C3 and C4; MPGN has low complement (C3 alone in type II / dense deposit disease, both C3 and C4 in type I).
Watch it explained
The repair move
For glomerular disease, read the light microscopy phrase and the complement level together. Spike-and-dome on silver stain plus normal complement plus pure nephrotic syndrome equals membranous (check anti-PLA2R antibody for primary disease, rule out hepatitis B, SLE, syphilis, solid-tumor adenocarcinoma, NSAIDs, gold, or penicillamine as secondary triggers; start ACE inhibitor and anticoagulate if albumin under 2.5 g/dL given high VTE risk). Tram-track basement membrane plus low complement plus mixed nephrotic-nephritic presentation equals MPGN (look for hepatitis C with cryoglobulinemia in type I, or C3 nephritic factor in type II dense deposit disease).
Try a free question
CoreAn adult has nephrotic syndrome and kidney biopsy shows diffuse capillary wall thickening with subepithelial deposits producing a spike-and-dome pattern. Which diagnosis is most likely?
Show answer and explanation
Answer: A. Membranous nephropathy. Subepithelial spike-and-dome deposits are classic for membranous nephropathy.
Why the other choices are tempting
- B. MPGN produces tram-track splitting and often mixed nephritic/nephrotic features.
- C. Minimal change disease has normal light microscopy.
- D. FSGS has focal segmental sclerosis.
- E. PSGN is nephritic with low complement after infection.
Flashcards
Tap a card to flip it.
What is the fastest separator for Membranous nephropathy vs Membranoproliferative GN?
Membranous is subepithelial spike-and-dome nephrotic disease; MPGN is subendothelial/mesangial tram-track mixed disease.
What clue should make you choose Membranous nephropathy?
Adult nephrotic syndrome with diffuse capillary wall thickening and spike-and-dome deposits.
Quick answers
What is the fastest way to tell Membranous nephropathy from Membranoproliferative GN?
Membranous is subepithelial spike-and-dome nephrotic disease; MPGN is subendothelial/mesangial tram-track mixed disease.
What is the key clue for Membranous nephropathy?
Adult nephrotic syndrome with diffuse capillary wall thickening and spike-and-dome deposits.
What is the key clue for Membranoproliferative GN?
Mixed nephritic-nephrotic picture with subendothelial/mesangial deposits and tram-track basement membrane splitting.
What is the common trap with Membranous nephropathy vs Membranoproliferative GN?
Both names contain membrane and both are immune-complex glomerulonephritides, which is what trips students up. The biopsy phrase fixes the answer. Spike-and-dome appearance on Jones silver stain with subepithelial deposits equals membranous nephropathy (pure nephrotic syndrome with very high proteinuria and high venous thromboembolism risk, especially renal vein thrombosis). Tram-track double contour basement membrane with subendothelial and mesangial deposits equals membranoproliferative GN (mixed nephrotic-nephritic presentation with LOW complement). The complement level is the fastest split: membranous has normal C3 and C4; MPGN has low complement (C3 alone in type II / dense deposit disease, both C3 and C4 in type I).