Table 1.
Baseline patient characteristics.
| Biopsy group | early (n = 14) | intermediate (n = 18) | late (n = 16) | P-value |
|---|---|---|---|---|
| Epidemiological parameters | ||||
| Age (years) | 56 ± 13 | 51 ± 15 | 58 ± 10 | 0.303 |
| Male sex, n (%) | 10 (71%) | 12 (67%) | 9 (56%) | 0.668 |
| Systolic blood pressure (mmHg) | 134 ± 10 | 140 ± 13 | 138 ± 21 | 0.711 |
| Diastolic blood pressure (mmHg) | 76 ± 9 | 82 ± 14 | 81 ± 11 | 0.552 |
| Antihypertensive medication, n (% yes) | 13 (93%) | 16 (89%) | 14 (88%) | 0.885 |
| Tx-associated parameters | ||||
| Time from Tx to biopsy (TxBx, years) | 0.3 (0.3) | 3.9 (4.0) | 14.2 (7.4) | <0.001 |
| Previous transplantation, n (%) | 4 (29%) | 5 (28%) | 2 (13%) | 0.478 |
| HLA serotype mismatch, n (A + B + DR) | 4 (3) | 3 (2) | 3 (1) | 0.237 |
| Current CDC PRA ≥ 40%, n (% yes) | 1/6 (17%) | 2/14 (14%) | 1/13 (8%) | 0.812 |
| Tacrolimus, n (% yes) | 13/14 (93%) | 10/18 (56%) | 1/15 (7%) | <0.001 |
| Cyclosporine A, n (% yes) | 0 (0%) | 7 (39%) | 14 (88%) | <0.001 |
| MMF or MPA, n (% yes) | 13/14 (93%) | 16/18 (89%) | 13/15 (87%) | 0.861 |
| Steroids n (% yes) | 13/13 (100%) | 18/18 (100%) | 12/15 (80%) | 0.036 |
| Donor specific antibodies, n (% yes) | 6 (43%) | 13 (72%) | 14 (88%) | 0.051 |
| Borderline lesions, n (% yes) | 1 (7%) | 4 (22%) | 0 (0%) | 0.080 |
| TCMR, n (% yes) | 2 (14%) | 3 (17%) | 0 (0%) | 0.276 |
| ABMR, n (% yes) | 2 (14%) | 5 (28%) | 8 (50%) | 0.276 |
| IFTA score (ci + ct) | 2 (5) | 2 (3) | 3 (3) | 0.150 |
| Kidney and RAS parameters | ||||
| Creatinine (mg/dL) | 2.0 ± 0.7 | 1.8 ± 0.7 | 1.8 ± 0.8 | 0.800 |
| eGFR-MDRD (mL/min/1.73 m²) | 37 ± 15 | 43 ± 21 | 40 ± 15 | 0.599 |
| Urinary P/C ratio (mg/g) | 326 ± 341 | 1152 ± 2175 | 747 ± 1235 | 0.346 |
| Renin (µU/mL) | 23 (71) | 44 (67) | 73 (83) | 0.197 |
| Aldosterone (pg/mL) | 134 ± 64 | 139 ± 94 | 125 ± 97 | 0.911 |
| ACE (U/l) | 8 (13) | 13 (19) | 13 (38) | 0.373 |
| Sodium (mmol/l) | 140 ± 3 | 140 ± 2 | 140 ± 2 | 0.872 |
| Potassium (mmol/l) | 4.8 ± 0.5 | 4.4 ± 0.4 | 4.6 ± 0.4 | 0.145 |
Data are shown as mean ± SD or median (inter-quartile range).
Groups were compared using ANOVA (for continuous variables), Kruskal-Wallis test (for TxBx) or Chi-squared test (for categorial variables). Renin and ACE was log-transformed prior to testing.
ABMR, antibody-mediated rejection; Bx, biopsy; CDC, complement-dependent cytotoxicity; Chronic renal pathology in the interstitium (ci), tubules (ct).
DSA, donor-specific antibody; eGFR, estimated glomerular filtration rate; HLA, human leukocyte antigen; IFTA, interstitial fibrosis and tubular atrophy, MMF, Mycophenolate mofetil, MPA Mycophenolic acid; P/C, protein/creatinine; TCMR, T-cell mediated rejection; Tx, transplantation.