Table 1.
Pathological findings in each subtype of C3 glomerulopathy and three cases of C3 dominant idiopathic MPGN.
| Type | Age | Gender | Ethnicity | LM findings | IF findings | EM findings | Complement profile | Genetic mutations associated | Acquired | Peak UPC | Peak sCr |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Classic C3 GN | MPGN, TMA, MP, DEP | C3 > Ig 2:1 | Varies, may have deposits | Possible increased activation | FH, FB,FI, C3,C5, THBD, PLS, MCP, DAGKE | C3/C4/C5 Nef | Inc | Inc | |||
| DDD | MPGN, TMA, Crescentic GN | C3 > Ig 2:1 | Numerous dense deposits | Possible increased activation | FH, FB,FI, C3,C5, THBD, PLS, MCP, DAGKE | C3/C4/C5 Nef | Inc | Inc | |||
| C3 Dom iMPGN | MPGN, TMA | C3 > Ig 2:1 | Sub End, sub Ep deposits | Possible increased activation | FH, FB,FI, C3,C5, THBD, PLS, MCP, DAGKE | C3/C4/C5 Nef | Inc | Inc | |||
| Case 1 iMPGN | 41 | F | Hispanic | MPGN, Endothelial swelling, Crescents | C3 > Ig | Sub End, sub Ep deposits | Low C3, normal sC5b-9 | None found | None | 4–6 g protein/g creatinine | 3mg/dL |
| Case 2 C3 Dom MPGN | 22 | F | Asian | MPGN | C3 only | Sub End, sub Ep deposits | 120–160% of normal sC5b-9 | Not done | Anti CFH Ab | 1–2 g protein/g creatinine | 0.5 mg/dL |
| Case 3 C3 Dom MPGN | 25 | F | Hispanic | MPGN, DDD, Crescents | C3 > Ig | Dense deposits | Initially normal then decreased C3, C4 | None found | None | 9 g protein/g creatinine | 15 mg/dl |
Anti CFH Ab, anti-complement Factor H antibody; C3G, C3 glomerulopathy; C3 Dom MPGN, C3 dominant membranoproliferative glomerulonephritis; CH50, total complement; DGKE, diacylglycerol kinase epsilon; DDD, dense deposit disease; DEP, diffuse endocapillary proliferative pattern; EM, electron microscopy; F, female; FH, factor H; FB, factor B; FI, factor I; g, gram; GN, glomerulonephritis; Inc, increased; iMPGN, idiopathic membranoproliferative glomerulonephritis; IF, immunofluorescence; Ig, immunoglobulin; iMPGN, idiopathic membranoproliferative glomerulonephritis; LM, light microscopy; M, male; MCP, membrane cofactor protein; mg/dL, milligram/deciliter; MP, mesangial proliferative pattern; MPGN, membranoproliferative glomerulonephritis [Type I]; NF, nephritic factor; PLS, plasminogen, sCr, serum creatinine [mg/dL]; Sub End, subendothelial; Sub Ep, subepithelial; SMAC, soluble membrane attack complex; THBD, thrombomodulin; TMA, thrombotic microangiopathy; UPC, urine protein/creatinine ratio [g/g creatinine].