Table 2.

Histopathologic findings in the C3 glomerulopathy cohort

FeatureTotal (N=80)DDD (n=21)C3GN (n=59)P Value
Light microscopy findings
 Pattern of injury
  Mesangial proliferative GN17 (21)3 (14)14 (24)0.11
  Diffuse endocapillary proliferative GN12 (15)1 (5)11 (19)
  Crescentic GN7 (9)4 (19)3 (5)
  Membranoproliferative GN44 (55)13 (62)31 (52)
 Global sclerosis (% glomeruli)
  Absent37 (46)14 (66.5)23 (39)0.05
  <5040 (50)6 (28.5)34 (58)
  >503 (4)1 (5)2 (3)
 Crescents present (%)
  None49 (61)9 (43)40 (68)0.05
  <5024 (30)8 (38)16 (27)
  ≥507 (9)4 (19)3 (5)
 Interstitial fibrosis (%)
  None25 (31)14 (67)11 (19)<0.001
  1–2530 (38)3 (14)27 (46)
  26–5017 (21)4 (19)13 (22)
  >508 (10)0 (0)8 (13)
 Arteriolar sclerosis
  None43 (54)18 (85.5)25 (42.4)0.003
  Mild21 (26)2 (9.5)19 (32.2)
  Moderate12 (15)1 (5)12 (20.4)
  Severe4 (5)0 (0)3 (5)
Immunohistology
 C3 in mesangium6 (8)1 (5)5 (8.5)0.43
 C3 in capillary wall21 (26)8 (38)13 (22)
 C3 both53 (66)12 (57)41 (69.5)
 C3 and no IgM41 (51)7 (33)34 (58)0.02
 C3 and IgM trace8 (10)5 (24)3 (5)
 C3 and IgM 1+31 (39)9 (43)22 (37)
Electron microscopy findings
 Mesangial deposits57 (71)8 (38)49 (83)<0.001
 Subepithelial humps28 (35)4 (19)24 (41)0.15
 Subepithelial deposits (any)39 (49)4 (19)36 (61)<0.001
 Subendothelial deposits45 (56)3 (14)42 (71)<0.001
 Intramembranous deposits, non-DDD28 (35)2 (9.5)29 (49)<0.001
 Intramembranous deposits, DDD21 (26)21 (100)0 (0)<0.001
 Deposits tubular basement membrane2 (3)2 (9.5)0 (0)<0.001
 Deposits Bowman’s capsule2 (3)2 (9.5)0 (0)<0.001
  • Data are presented as n (%). P values represent the differences between the DDD and C3GN subgroups. DDD, dense deposit disease.