Table 2.
Pathologic features, according to immune-complex glomerulopathy not otherwise specified (ICG-NOS) group
| Total (n = 28) | Full-house (+IgG/+IgM/+IgA/+C3/+C1q) (n = 3) |
Quasi-full-house (+IgG/+C3/+C1q) (n = 10) |
IgA-rich (IgA-codominant) (n = 3) |
C1q-rich (−IgG/+C1q) (n = 6) |
C1q-poor (+IgG/−C1q) (n = 6) |
P value | |
|---|---|---|---|---|---|---|---|
| Light microscopy | |||||||
| Number of glomeruli, median (range) | 16 (4–30) | 20 (10–26) | 17 (4–28) | 14 (6–21) | 16 (6–22) | 15 (12–30) | 0.34 |
| Glomerular injury pattern, n (%)a | |||||||
| Mesangial hyperplasia-proliferation | 18 (64) | 2 (67) | 5 (50) | 1 (33) | 5 (83) | 5 (83) | 0.40 |
| Capillary wall duplication | 7 (25) | 0 (0) | 1 (10) | 1 (33) | 3 (50) | 2 (33) | 0.34 |
| Focal and segmental glomerulosclerosis | 7 (25) | 1 (33) | 3 (30) | 1 (33) | 1 (17) | 1 (17) | 0.94 |
| Normal | 8 (29) | 1 (33) | 4 (40) | 2 (67) | 0 (0) | 1 (17) | 0.94 |
| % Global glomerulosclerosis, median (range) | 5.5 (0–58) | 0 (0–4) | 9 (0–50) | 7 (0–14) | 7 (0–50) | 4.5 (0–58) | 0.53 |
| % Interstitial fibrosis/tubular atrophy, median (range) | 10 (0–95) | 0 (0–0) | 13 (0–50) | 17.5 (5–30) | 20 (0–70) | 15 (0–95) | 0.50 |
| Histologic antibody-mediated rejection, n (%) | 0.74 | ||||||
| Glomerulitis + peritubular capillaritis | 12 (43) | 1 (33) | 3 (30) | 1 (33) | 4 (67) | 3 (50) | |
| Glomerulitis only | 3 (11) | 0 (0) | 1 (10) | 0 (0) | 0 (0) | 2 (33) | |
| Peritubular capillaritis only | 5 (18) | 1 (33) | 2 (20) | 1 (1) | 1 (17) | 0 (0) | |
| None | 8 (29) | 1 (33) | 4 (40) | 1 (33) | 1 (17) | 1 (17) | |
| Histologic T-cell–mediated rejection, n (%) | 0.07 | ||||||
| Banff 1A | 1 (4) | 1 (33) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | |
| Borderline | 9 (32) | 0 (0) | 5 (50) | 1 (33) | 3 (50) | 0 (0) | |
| None | 18 (64) | 2 (67) | 5 (50) | 2 (67) | 3 (50) | 6 (100) | |
| No histologic rejection | 8 (29) | 1 (33) | 2 (20) | 1 (33) | 1 (17) | 1 (17) | 0.74 |
| Immunofluorescence microscopy | |||||||
| IgG, median (range) | 1.0 (0.0–4.0) | 2.0 (2.0–4.0) | 1.75 (0.5–2.0) | 2.0 (1.0–3.0) | 0.0 (0.0–0.0) | 1.0 (1.0–3.0) | 0.002 |
| IgA, median (range) | 0.0 (0.0–3.0) | 1.0 (0.5–3.0) | 0.0 (0.0–0.0) | 3.0 (1.5–3.0) | 0.0 (0.0–0.5) | 0.0 (0.0–0.0) | <0.001 |
| IgM, median (range) | 1.0 (0.0–3.0) | 2.5 (1.5–3.0) | 1.0 (0.0–2.0) | 0.5 (0.0–3.0) | 1.0 (0.5–2.0) | 0.8 (0.0–2.0) | 0.08 |
| C1q, median (range) | 1.0 (0.0–3.0) | 2.5 (1.0–3.0) | 1.0 (0.5–3.0) | 0 (0.0–3.0) | 1.0 (1.0–2.0) | 0.0 (0.0–0.0) | <0.001 |
| C3, median (range) | 0.75 (0.0–2.0) | 1.0 (1.0–1.0) | 1.0 (0.5–2.0) | 0.5 (0.0–2.0) | 0.0 (0.0–1.0) | 0.0 (0.0–2.0) | 0.06 |
| C4d, peritubular capillary, n (%) | 0.69 | ||||||
| positive | 5 (18) | 1 (33) | 0 (0) | 1 (33) | 2 (33) | 1 (17) | |
| Negative | 22 (79) | 2 (67) | 9 (90) | 2 (67) | 4 (67) | 5 (83) | |
| Not done | 1 (4) | 0 (0) | 1 (0) | 0 (0) | 0 (0) | 0 (0) | |
| C4d, glomerular, n (%) | 0.25 | ||||||
| Mesangial | 7 (25) | 0 (0) | 5 (50) | 1 (10) | 0 (0) | 1 (17) | |
| Capillary wall | 12 (43) | 1 (33) | 2 (20) | 2 (20) | 5 (83) | 2 (33) | |
| Negative | 7 (25) | 2 (67) | 2 (20) | 0 (0) | 1 (17) | 2 (33) | |
| Not done | 1 (4) | 0 (0) | 1 (10) | 0 (0) | 0 (0) | 0 (0) | |
| Electron microscopy | |||||||
| Electron microscopy performed, n (%) | 21 (75) | 3 (100) | 8 (80) | 1 (33) | 4 (67) | 5 (83) | 0.36 |
| Deposit location, n (%) | 0.34 | ||||||
| Mesangial | 14 (67) | 2 (67) | 6 (75) | 0 (0) | 2 (50) | 3 (60) | |
| Mesangial and subendothelial | 5 (24) | 1 (33) | 2 (25) | 1 (100) | 1 (25) | 0 (0) | |
| None | 3 (14) | 0 (0) | 0 (0) | 0 (0) | 1 (25) | 2 (40) | |
| Feature of transplant glomerulopathy (glomerular basement membrane duplication or mesangiolysis) | 6 (29) | 1 (33) | 2 (25) | 0 (0) | 2 (50) | 1 (20) | 0.75 |
| Percent podocyte effacement, median (range) | 10 (0–100) | 5 (5–10) | 10 (0–80) | 30 (30–30) | 10 (0–10) | 10 (0–100) | 0.73 |
a
Some biopsies demonstrated more than 1 glomerular injury pattern.