Table 1.
Patient characteristics
| Variable | Non-aHUS patients, N = 13 | aHUS patients, N = 13 | P-value |
|---|---|---|---|
| Female gender, n (%) | 6 (46.2%) | 9 (69.2%) | 0.428 |
| Age (yrs) | 42 (27–60) | 54 (35–69) | 0.120 |
| Primary kidney disease (n) | Diabetic nephropathy, n = 2 IgA nephropathy, n = 4 ANCA vasculitis, n = 1 Cystinosis, n = 1 Fibrillary glomerulonephritis, n = 1 Membranous Nephropathy n = 1 Nephronophthisis, n = 1 Vesico-urethral reflux, n = 1 Autosomal dominant polycystic kidney disease, n = 1 |
Atypical HUS | n.a. |
| Number of previous kidney transplants | 0 (0–2) | 1 (0–2) | 0.311 |
| Genetic complement variant (n;%) | # | C3 variant 7 (53.8%) (R161W n = 6) CHF variant 3 (23.1%) MCP variant 1 (7.7%) No variant 2 (15.4%) |
n.a. |
| Time since (last) kidney transplantation (yrs) | 5.8 (1.6–11.7) | 5.9 (0.25–14.1) | 0.998 |
| Type of donor, n (%) | Living donor, 11 (84.6%) Deceased donor, 2 (15.4%) |
Living donor, 10 (76.9%) Deceased donor, 3 (23.1%) |
1.000 |
| HLA Mismatch | 3 (2–6) (n=12) | 4 (0–6) (n=13) | 0.247 |
| HLA antibodies positive, n (%) | 5 (38.5%) | 4 (30.8%) | 0.500 |
| DSA positive, n (%) | 5 (38.5%) | 3 (23.1%) | 0.673 |
| IS regimen at sample withdrawal (n) | Pred/TAC 7 Pred/TAC/MMF 4 Pred/TAC/AZA 1 TAC/MMF 1 |
Pred/TAC 3 Pred/TAC/MMF 6 Pred/TAC/AZA 1 TAC/AZA 1 TAC/MMF 1 Sirolimus/pred 1 |
0.590 |
| Use of CNI, n (%) | 13 (100%) | 12 (92.3%) | 1.000 |
| TAC trough level at sample withdrawal (ug/l) | 6.2 (3.1–10.3) | 5.9 (4.5–7) | 0.506 |
| Patients with rejection, n (%) | 3 (23.1%) | 3 (23.1%) | 1.000 |
| Time since rejection (mos) | 18.4 (18.0–106) | 134.1 (45.1–168.5) | 0.127 |
| aHUS recurrence after last Ktx, n (%) | n.a. | 0 (0%) | n.a. |
| Treatment with eculizumab, n (%) | n.a. | 0 (0%) | n.a. |
| C5b-9 deposition on resting HMEC (%) | 121.0 (75–200) | 136.0 (93–382) | 0.614 |
| C5b-9 deposition on activated HMEC (%) | 170.0 (113–260) | 196.0 (99–388) | 0.705 |
| sCR (μmol/l)a | 123.0 (77–169) | 100.0 (76–176) | 0.990 |
| eGFR (ml/min per 1.73 m2)a | 61.0 (37–92) | 61.0 (28–86) | 0.517 |
| UPCRa (g/10 mmol) | 0.10 (0.08–0.46) | 0.13 (0–0.86) | 0.479 |
| Hba (mmol/l) | 8.2 (7–9) | 7.4 (6.6–10) | 0.057 |
| Thrombocytesa (x 10ꝰ/l) | 205 (151–302) | 206 (140–286) | 0.975 |
| LDHa (u/l) | 201 (165–256) (n=6) | 206 (156–292) (n=11) | 0.737 |
| C3a (mg/l) | 983 (761–1359) (n=13) | 972 (772–1220) (n=12) | 0.851 |
| C3d/C3 ratioa | 5.1 (3–9.2) (n=13) | 5.7 (3.1–10.1) (n=12) | 0.230 |
| Follow-up after sample collection (mos) | 15.6 (6.2–18.6) | 19.7 (10.8–21.1) | 0.010 |
| sCR at last follow-up (μmol/l) | 127.0 (79–162) | 107.0 (76–180) | 0.792 |
| eGFR (CKD-EPI) at last follow-up (ml/min per 1.73 m2) | 59.0 (39–96) | 57.0 (26–84) | 0.594 |
| UPCR at last follow-up (g/10 mmol) | 0.10 (0.05–0.86) | 0.14 (0.08–0.69) | 0.186 |
aHUS, atypical hemolytic uremic syndrome; Hb, hemoglobin; CNI, calcineurin inhibitors; eGFR, estimated glomerular filtration rate (CKD-EPI formula); Ktx, kidney transplantation; LDH, lactate dehydrogenase (normal <250 u/l); n.a., not applicable; sCr, serum creatinine; TAC, tacrolimus trough level; UPCR, urine protein creatinine ratio; DSA, donor-specific antibody
Results are given as median (range).
a
Data obtained at the time of sample collection.
#
in 4 control patients with elevated C5b-9 deposition on resting HMEC genetic analysis was performed: in one patient a benign CFB variant was found.